diff --git a/backend/apis/__init__.py b/backend/apis/__init__.py
index 2909db3..48e6726 100755
--- a/backend/apis/__init__.py
+++ b/backend/apis/__init__.py
@@ -1,10 +1,10 @@
 from flask import Blueprint
 from flask_restplus import Api
 
-from .ufl import api as ufl
-from .private import api as private
 from .analyze import api as analyze
 from .downloadLineagesInfo import api as downloadLineagesInfo
+from .private import api as private
+from .ufl import api as ufl
 
 enable_doc = True
 
diff --git a/backend/apis/analyze.py b/backend/apis/analyze.py
index cf2092d..b981404 100644
--- a/backend/apis/analyze.py
+++ b/backend/apis/analyze.py
@@ -1,25 +1,22 @@
 from __future__ import print_function
 
+import copy
 import http
 import json
-import pandas as pd
-import copy
-
-import statsmodels.stats.multitest as sms
-from scipy.stats import binom, chi2_contingency
-from flask_restplus import Namespace, Resource
-
 from datetime import datetime, timedelta
 from threading import Timer
 
+import pandas as pd
+import statsmodels.stats.multitest as sms
+from flask_restplus import Namespace, Resource
 from pymongo import MongoClient
+from scipy.stats import chi2_contingency
 
 from .downloadLineagesInfo import dict_lineage_mutation
 
 api = Namespace('analyze', description='analyze')
 
 uri = "mongodb://localhost:23456/gcm_gisaid"
-# uri = "mongodb://localhost:23457/gcm_gisaid"
 client = MongoClient(uri)
 db = client.gcm_gisaid
 
@@ -2584,15 +2581,17 @@ def post(self):
                 if key == 'minDate':
                     start_date = datetime.strptime(f"{query_background[key]}", '%Y-%m-%d')
                     where_part_background_overlapping['collection_date']['$gte'] = start_date
-                    if where_part_target_overlapping['collection_date']['$gte'] < start_date\
-                            < where_part_target_overlapping['collection_date']['$lte']:
-                        where_part_target_overlapping['collection_date']['$gte'] = start_date
+                    if "$lte" in where_part_target_overlapping['collection_date']:
+                        if where_part_target_overlapping['collection_date']['$gte'] < start_date\
+                                < where_part_target_overlapping['collection_date']['$lte']:
+                            where_part_target_overlapping['collection_date']['$gte'] = start_date
                 elif key == 'maxDate':
                     stop_date = datetime.strptime(f"{query_background[key]}", '%Y-%m-%d')
                     where_part_background_overlapping['collection_date']['$lte'] = stop_date
-                    if where_part_target_overlapping['collection_date']['$gte'] < stop_date \
-                            < where_part_target_overlapping['collection_date']['$lte']:
-                        where_part_target_overlapping['collection_date']['$lte'] = stop_date
+                    if "$lte" in where_part_target_overlapping['collection_date']:
+                        if where_part_target_overlapping['collection_date']['$gte'] < stop_date \
+                                < where_part_target_overlapping['collection_date']['$lte']:
+                            where_part_target_overlapping['collection_date']['$lte'] = stop_date
 
                 elif key == 'toExclude':
                     for fieldToExclude in query_background[key]:
diff --git a/backend/apis/analyze_file.py b/backend/apis/analyze_file.py
index 439343b..ad07616 100644
--- a/backend/apis/analyze_file.py
+++ b/backend/apis/analyze_file.py
@@ -1,35 +1,18 @@
 from __future__ import print_function
+
+import collections
 # %config Completer.use_jedi = False
 import datetime
-import os
-import re
-
-import requests
-import io
 import http.client
+import io
+import itertools
 import json
-
-import pandas as pd
 from collections import defaultdict
-from Bio import SeqIO
 from io import StringIO
-from Bio import Align, Seq, pairwise2
-from Bio.Data import CodonTable
-import numpy as np
-import itertools
-import collections
-import logomaker
-import tqdm
-import psycopg2
-import matplotlib.pyplot as plt
-
-from ipywidgets import interact, interactive, fixed, interact_manual
-import ipywidgets as widgets
-from IPython.core.display import HTML
 
+import pandas as pd
 from flask_restplus import Namespace, Resource
 
-
 api = Namespace('analyze_file', description='analyze_file')
 
 
diff --git a/backend/apis/analyze_file_example.py b/backend/apis/analyze_file_example.py
index 5f65a89..7d1c162 100644
--- a/backend/apis/analyze_file_example.py
+++ b/backend/apis/analyze_file_example.py
@@ -1,31 +1,12 @@
 from __future__ import print_function
-# %config Completer.use_jedi = False
 
-import requests
 import io
-import http.client
-import json
-
-import pandas as pd
 from collections import defaultdict
-from Bio import SeqIO
-from io import StringIO
-from Bio import Align, Seq, pairwise2
-from Bio.Data import CodonTable
-import numpy as np
-import itertools
-import collections
-import logomaker
-import tqdm
-import psycopg2
-import matplotlib.pyplot as plt
-
-from ipywidgets import interact, interactive, fixed, interact_manual
-import ipywidgets as widgets
-from IPython.core.display import HTML
 
 from flask_restplus import Namespace, Resource
 
+# %config Completer.use_jedi = False
+
 
 api = Namespace('analyze_file_example', description='analyze_file_example')
 
diff --git a/backend/apis/downloadLineagesInfo.py b/backend/apis/downloadLineagesInfo.py
index 74d6290..cf8bea3 100644
--- a/backend/apis/downloadLineagesInfo.py
+++ b/backend/apis/downloadLineagesInfo.py
@@ -1,12 +1,10 @@
 import json
-
-import requests
-import lxml.html
-import pandas as pd
-
 from datetime import datetime, timedelta
 from threading import Timer
 
+import lxml.html
+import pandas as pd
+import requests
 from flask_restplus import Namespace
 
 api = Namespace('downloadLineagesInfo', description='downloadLineagesInfo')
diff --git a/backend/apis/private.py b/backend/apis/private.py
index 340e31c..e65546b 100644
--- a/backend/apis/private.py
+++ b/backend/apis/private.py
@@ -1,35 +1,23 @@
 from __future__ import print_function
+
+import collections
 # %config Completer.use_jedi = False
 import datetime
-import os
-import re
-
-import requests
-import io
 import http.client
+import io
+import itertools
 import json
+import os
+from collections import defaultdict
+from io import StringIO
 
 import pandas as pd
-from collections import defaultdict
+import tqdm
 from Bio import SeqIO
-from io import StringIO
-from Bio import Align, Seq, pairwise2
+from Bio import pairwise2
 from Bio.Data import CodonTable
-import numpy as np
-import itertools
-import collections
-import logomaker
-import tqdm
-import psycopg2
-import matplotlib.pyplot as plt
-
-from ipywidgets import interact, interactive, fixed, interact_manual
-import ipywidgets as widgets
-from IPython.core.display import HTML
-
 from flask_restplus import Namespace, Resource
 
-
 api = Namespace('private', description='private')
 
 
diff --git a/backend/apis/ufl.py b/backend/apis/ufl.py
index d94cc79..11f3be1 100644
--- a/backend/apis/ufl.py
+++ b/backend/apis/ufl.py
@@ -1,12 +1,9 @@
+import http.client
 import json
-import urllib
 
 import requests
-import http.client
-
 from flask_restplus import Namespace, Resource
 
-
 api = Namespace('ufl', description='ufl')
 
 http.client._MAXLINE = 655360
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/certifi/__init__.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/certifi/__init__.py
index 4e5133b..884ae37 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/certifi/__init__.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/certifi/__init__.py
@@ -1,3 +1 @@
-from .core import contents, where
-
 __version__ = "2020.11.08"
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/__init__.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/__init__.py
index 0f9f820..8437361 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/__init__.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/__init__.py
@@ -16,9 +16,7 @@
 ######################### END LICENSE BLOCK #########################
 
 
-from .compat import PY2, PY3
 from .universaldetector import UniversalDetector
-from .version import __version__, VERSION
 
 
 def detect(byte_str):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/big5prober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/big5prober.py
index 98f9970..f663243 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/big5prober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/big5prober.py
@@ -25,9 +25,9 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import Big5DistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import BIG5_SM_MODEL
 
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/chardistribution.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/chardistribution.py
index c0395f4..ad2a6b7 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/chardistribution.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/chardistribution.py
@@ -25,14 +25,14 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .euctwfreq import (EUCTW_CHAR_TO_FREQ_ORDER, EUCTW_TABLE_SIZE,
-                        EUCTW_TYPICAL_DISTRIBUTION_RATIO)
+from .big5freq import (BIG5_CHAR_TO_FREQ_ORDER, BIG5_TABLE_SIZE,
+                       BIG5_TYPICAL_DISTRIBUTION_RATIO)
 from .euckrfreq import (EUCKR_CHAR_TO_FREQ_ORDER, EUCKR_TABLE_SIZE,
                         EUCKR_TYPICAL_DISTRIBUTION_RATIO)
+from .euctwfreq import (EUCTW_CHAR_TO_FREQ_ORDER, EUCTW_TABLE_SIZE,
+                        EUCTW_TYPICAL_DISTRIBUTION_RATIO)
 from .gb2312freq import (GB2312_CHAR_TO_FREQ_ORDER, GB2312_TABLE_SIZE,
                          GB2312_TYPICAL_DISTRIBUTION_RATIO)
-from .big5freq import (BIG5_CHAR_TO_FREQ_ORDER, BIG5_TABLE_SIZE,
-                       BIG5_TYPICAL_DISTRIBUTION_RATIO)
 from .jisfreq import (JIS_CHAR_TO_FREQ_ORDER, JIS_TABLE_SIZE,
                       JIS_TYPICAL_DISTRIBUTION_RATIO)
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/charsetgroupprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/charsetgroupprober.py
index 8b3738e..4f14398 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/charsetgroupprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/charsetgroupprober.py
@@ -25,8 +25,8 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .enums import ProbingState
 from .charsetprober import CharSetProber
+from .enums import ProbingState
 
 
 class CharSetGroupProber(CharSetProber):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/eucjpprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/eucjpprober.py
index 20ce8f7..9b6fe36 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/eucjpprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/eucjpprober.py
@@ -25,11 +25,11 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .enums import ProbingState, MachineState
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import EUCJPDistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .enums import ProbingState, MachineState
 from .jpcntx import EUCJPContextAnalysis
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import EUCJP_SM_MODEL
 
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euckrprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euckrprober.py
index 345a060..f650529 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euckrprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euckrprober.py
@@ -25,9 +25,9 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import EUCKRDistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import EUCKR_SM_MODEL
 
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euctwprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euctwprober.py
index 35669cc..d76076a 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euctwprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/euctwprober.py
@@ -25,11 +25,12 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import EUCTWDistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import EUCTW_SM_MODEL
 
+
 class EUCTWProber(MultiByteCharSetProber):
     def __init__(self):
         super(EUCTWProber, self).__init__()
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/gb2312prober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/gb2312prober.py
index 8446d2d..502e4a8 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/gb2312prober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/gb2312prober.py
@@ -25,11 +25,12 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import GB2312DistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import GB2312_SM_MODEL
 
+
 class GB2312Prober(MultiByteCharSetProber):
     def __init__(self):
         super(GB2312Prober, self).__init__()
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/mbcsgroupprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/mbcsgroupprober.py
index 530abe7..c42d1cb 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/mbcsgroupprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/mbcsgroupprober.py
@@ -27,15 +27,15 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
+from .big5prober import Big5Prober
 from .charsetgroupprober import CharSetGroupProber
-from .utf8prober import UTF8Prober
-from .sjisprober import SJISProber
+from .cp949prober import CP949Prober
 from .eucjpprober import EUCJPProber
-from .gb2312prober import GB2312Prober
 from .euckrprober import EUCKRProber
-from .cp949prober import CP949Prober
-from .big5prober import Big5Prober
 from .euctwprober import EUCTWProber
+from .gb2312prober import GB2312Prober
+from .sjisprober import SJISProber
+from .utf8prober import UTF8Prober
 
 
 class MBCSGroupProber(CharSetGroupProber):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sbcsgroupprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sbcsgroupprober.py
index 98e95dc..daa10d6 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sbcsgroupprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sbcsgroupprober.py
@@ -27,17 +27,17 @@
 ######################### END LICENSE BLOCK #########################
 
 from .charsetgroupprober import CharSetGroupProber
-from .sbcharsetprober import SingleByteCharSetProber
+from .hebrewprober import HebrewProber
+from .langbulgarianmodel import Latin5BulgarianModel, Win1251BulgarianModel
 from .langcyrillicmodel import (Win1251CyrillicModel, Koi8rModel,
                                 Latin5CyrillicModel, MacCyrillicModel,
                                 Ibm866Model, Ibm855Model)
 from .langgreekmodel import Latin7GreekModel, Win1253GreekModel
-from .langbulgarianmodel import Latin5BulgarianModel, Win1251BulgarianModel
+from .langhebrewmodel import Win1255HebrewModel
 # from .langhungarianmodel import Latin2HungarianModel, Win1250HungarianModel
 from .langthaimodel import TIS620ThaiModel
-from .langhebrewmodel import Win1255HebrewModel
-from .hebrewprober import HebrewProber
 from .langturkishmodel import Latin5TurkishModel
+from .sbcharsetprober import SingleByteCharSetProber
 
 
 class SBCSGroupProber(CharSetGroupProber):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sjisprober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sjisprober.py
index 9e29623..1094a93 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sjisprober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/sjisprober.py
@@ -25,12 +25,12 @@
 # 02110-1301  USA
 ######################### END LICENSE BLOCK #########################
 
-from .mbcharsetprober import MultiByteCharSetProber
-from .codingstatemachine import CodingStateMachine
 from .chardistribution import SJISDistributionAnalysis
+from .codingstatemachine import CodingStateMachine
+from .enums import ProbingState, MachineState
 from .jpcntx import SJISContextAnalysis
+from .mbcharsetprober import MultiByteCharSetProber
 from .mbcssm import SJIS_SM_MODEL
-from .enums import ProbingState, MachineState
 
 
 class SJISProber(MultiByteCharSetProber):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/utf8prober.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/utf8prober.py
index 6c3196c..5018474 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/utf8prober.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/chardet/utf8prober.py
@@ -26,12 +26,11 @@
 ######################### END LICENSE BLOCK #########################
 
 from .charsetprober import CharSetProber
-from .enums import ProbingState, MachineState
 from .codingstatemachine import CodingStateMachine
+from .enums import ProbingState, MachineState
 from .mbcssm import UTF8_SM_MODEL
 
 
-
 class UTF8Prober(CharSetProber):
     ONE_CHAR_PROB = 0.5
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/_backport/shutil.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/_backport/shutil.py
index 10ed362..01a7cd0 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/_backport/shutil.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/_backport/shutil.py
@@ -9,11 +9,12 @@
 
 """
 
+import fnmatch
 import os
-import sys
 import stat
+import sys
 from os.path import abspath
-import fnmatch
+
 try:
     from collections.abc import Callable
 except ImportError:
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/compat.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/compat.py
index c316fd9..c7df001 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/compat.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/compat.py
@@ -19,13 +19,9 @@
     from StringIO import StringIO
     string_types = basestring,
     text_type = unicode
-    from types import FileType as file_type
-    import __builtin__ as builtins
-    import ConfigParser as configparser
     from ._backport import shutil
-    from urlparse import urlparse, urlunparse, urljoin, urlsplit, urlunsplit
-    from urllib import (urlretrieve, quote as _quote, unquote, url2pathname,
-                        pathname2url, ContentTooShortError, splittype)
+    from urllib import (urlretrieve, quote as _quote, url2pathname,
+                        splittype)
 
     def quote(s):
         if isinstance(s, unicode):
@@ -33,20 +29,15 @@ def quote(s):
         return _quote(s)
 
     import urllib2
-    from urllib2 import (Request, urlopen, URLError, HTTPError,
-                         HTTPBasicAuthHandler, HTTPPasswordMgr,
-                         HTTPHandler, HTTPRedirectHandler,
-                         build_opener)
+
     if ssl:
         from urllib2 import HTTPSHandler
-    import httplib
     import xmlrpclib
     import Queue as queue
     from HTMLParser import HTMLParser
     import htmlentitydefs
     raw_input = raw_input
     from itertools import ifilter as filter
-    from itertools import ifilterfalse as filterfalse
 
     _userprog = None
     def splituser(host):
@@ -68,17 +59,10 @@ def splituser(host):
     import builtins
     import configparser
     import shutil
-    from urllib.parse import (urlparse, urlunparse, urljoin, splituser, quote,
-                              unquote, urlsplit, urlunsplit, splittype)
-    from urllib.request import (urlopen, urlretrieve, Request, url2pathname,
-                                pathname2url,
-                                HTTPBasicAuthHandler, HTTPPasswordMgr,
-                                HTTPHandler, HTTPRedirectHandler,
-                                build_opener)
+
     if ssl:
         from urllib.request import HTTPSHandler
     from urllib.error import HTTPError, URLError, ContentTooShortError
-    import http.client as httplib
     import urllib.request as urllib2
     import xmlrpc.client as xmlrpclib
     import queue
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/database.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/database.py
index 0a90c30..2d044cf 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/database.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/database.py
@@ -19,12 +19,11 @@
 
 from . import DistlibException, resources
 from .compat import StringIO
-from .version import get_scheme, UnsupportedVersionError
 from .metadata import (Metadata, METADATA_FILENAME, WHEEL_METADATA_FILENAME,
                        LEGACY_METADATA_FILENAME)
 from .util import (parse_requirement, cached_property, parse_name_and_version,
                    read_exports, write_exports, CSVReader, CSVWriter)
-
+from .version import get_scheme, UnsupportedVersionError
 
 __all__ = ['Distribution', 'BaseInstalledDistribution',
            'InstalledDistribution', 'EggInfoDistribution',
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/index.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/index.py
index 7a87cdc..5556d3e 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/index.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/index.py
@@ -18,7 +18,7 @@
 from . import DistlibException
 from .compat import (HTTPBasicAuthHandler, Request, HTTPPasswordMgr,
                      urlparse, build_opener, string_types)
-from .util import cached_property, zip_dir, ServerProxy
+from .util import zip_dir, ServerProxy
 
 logger = logging.getLogger(__name__)
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/locators.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/locators.py
index 12a1d06..2078f0b 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/locators.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/locators.py
@@ -6,12 +6,13 @@
 #
 
 import gzip
-from io import BytesIO
 import json
 import logging
 import os
 import posixpath
 import re
+from io import BytesIO
+
 try:
     import threading
 except ImportError:  # pragma: no cover
@@ -20,12 +21,12 @@
 
 from . import DistlibException
 from .compat import (urljoin, urlparse, urlunparse, url2pathname, pathname2url,
-                     queue, quote, unescape, string_types, build_opener,
+                     queue, quote, unescape, build_opener,
                      HTTPRedirectHandler as BaseRedirectHandler, text_type,
                      Request, HTTPError, URLError)
 from .database import Distribution, DistributionPath, make_dist
 from .metadata import Metadata, MetadataInvalidError
-from .util import (cached_property, parse_credentials, ensure_slash,
+from .util import (cached_property, ensure_slash,
                    split_filename, get_project_data, parse_requirement,
                    parse_name_and_version, ServerProxy, normalize_name)
 from .version import get_scheme, UnsupportedVersionError
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/manifest.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/manifest.py
index ca0fe44..66f6597 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/manifest.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/manifest.py
@@ -18,7 +18,6 @@
 from .compat import fsdecode
 from .util import convert_path
 
-
 __all__ = ['Manifest']
 
 logger = logging.getLogger(__name__)
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/markers.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/markers.py
index ee1f3e2..18e2be7 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/markers.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/markers.py
@@ -13,11 +13,10 @@
 # as ~= and === which aren't in Python, necessitating a different approach.
 
 import os
-import sys
 import platform
-import re
+import sys
 
-from .compat import python_implementation, urlparse, string_types
+from .compat import string_types
 from .util import in_venv, parse_marker
 
 __all__ = ['interpret']
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/metadata.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/metadata.py
index 6d5e236..69e2948 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/metadata.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/metadata.py
@@ -10,11 +10,10 @@
 from __future__ import unicode_literals
 
 import codecs
-from email import message_from_file
 import json
 import logging
 import re
-
+from email import message_from_file
 
 from . import DistlibException, __version__
 from .compat import StringIO, string_types, text_type
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/resources.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/resources.py
index 1884016..983427b 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/resources.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/resources.py
@@ -11,13 +11,12 @@
 import logging
 import os
 import pkgutil
-import shutil
 import sys
 import types
 import zipimport
 
 from . import DistlibException
-from .util import cached_property, get_cache_base, path_to_cache_dir, Cache
+from .util import cached_property, get_cache_base, Cache
 
 logger = logging.getLogger(__name__)
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/scripts.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/scripts.py
index 03f8f21..3e49634 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/scripts.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/scripts.py
@@ -4,12 +4,12 @@
 # Licensed to the Python Software Foundation under a contributor agreement.
 # See LICENSE.txt and CONTRIBUTORS.txt.
 #
-from io import BytesIO
 import logging
 import os
 import re
 import struct
 import sys
+from io import BytesIO
 
 from .compat import sysconfig, detect_encoding, ZipFile
 from .resources import finder
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/util.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/util.py
index 01324ea..a0ab73c 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/util.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/util.py
@@ -3,10 +3,8 @@
 # See LICENSE.txt and CONTRIBUTORS.txt.
 #
 import codecs
-from collections import deque
 import contextlib
 import csv
-from glob import iglob as std_iglob
 import io
 import json
 import logging
@@ -14,6 +12,9 @@
 import py_compile
 import re
 import socket
+from collections import deque
+from glob import iglob as std_iglob
+
 try:
     import ssl
 except ImportError:  # pragma: no cover
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/wheel.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/wheel.py
index 1e2c7a0..4a1613d 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/wheel.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/distlib/wheel.py
@@ -10,7 +10,6 @@
 import codecs
 import datetime
 import distutils.util
-from email import message_from_file
 import hashlib
 import imp
 import json
@@ -22,11 +21,12 @@
 import sys
 import tempfile
 import zipfile
+from email import message_from_file
 
 from . import __version__, DistlibException
 from .compat import sysconfig, ZipFile, fsdecode, text_type, filter
 from .database import InstalledDistribution
-from .metadata import (Metadata, METADATA_FILENAME, WHEEL_METADATA_FILENAME,
+from .metadata import (Metadata, WHEEL_METADATA_FILENAME,
                        LEGACY_METADATA_FILENAME)
 from .util import (FileOperator, convert_path, CSVReader, CSVWriter, Cache,
                    cached_property, get_cache_base, read_exports, tempdir)
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/__init__.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/__init__.py
index 847bf93..8b13789 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/__init__.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/__init__.py
@@ -1,2 +1 @@
-from .package_data import __version__
-from .core import *
+
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/codec.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/codec.py
index 98c65ea..2a0dfe8 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/codec.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/codec.py
@@ -1,7 +1,8 @@
-from .core import encode, decode, alabel, ulabel, IDNAError
 import codecs
 import re
 
+from .core import encode, decode, alabel, ulabel, IDNAError
+
 _unicode_dots_re = re.compile(u'[\u002e\u3002\uff0e\uff61]')
 
 class Codec(codecs.Codec):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/compat.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/compat.py
index 4d47f33..f8b91a8 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/compat.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/compat.py
@@ -1,4 +1,3 @@
-from .core import *
 from .codec import *
 
 def ToASCII(label):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/core.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/core.py
index 41ec5c7..5293a34 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/core.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/idna/core.py
@@ -1,8 +1,9 @@
-from . import idnadata
 import bisect
-import unicodedata
 import re
 import sys
+import unicodedata
+
+from . import idnadata
 from .intranges import intranges_contain
 
 _virama_combining_class = 9
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/__init__.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/__init__.py
index d6705e2..5b19b1c 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/__init__.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/__init__.py
@@ -1,14 +1,11 @@
 # coding: utf-8
-from ._version import version
-from .exceptions import *
-from .ext import ExtType, Timestamp
 
 import os
 import sys
 
 
 if os.environ.get("MSGPACK_PUREPYTHON") or sys.version_info[0] == 2:
-    from .fallback import Packer, unpackb, Unpacker
+    from .fallback import Packer, unpackb
 else:
     try:
         from ._cmsgpack import Packer, unpackb, Unpacker
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/ext.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/ext.py
index 8341c68..7a041a9 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/ext.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/ext.py
@@ -1,9 +1,8 @@
 # coding: utf-8
-from collections import namedtuple
 import datetime
-import sys
 import struct
-
+import sys
+from collections import namedtuple
 
 PY2 = sys.version_info[0] == 2
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/fallback.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/fallback.py
index 9f6665b..6a21437 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/fallback.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/msgpack/fallback.py
@@ -1,9 +1,8 @@
 """Fallback pure Python implementation of msgpack"""
 
-from datetime import datetime as _DateTime
-import sys
 import struct
-
+import sys
+from datetime import datetime as _DateTime
 
 PY2 = sys.version_info[0] == 2
 if PY2:
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py
index a536b03..f794910 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py
@@ -12,16 +12,16 @@
 - control_dir/output.json
   - {"return_val": ...}
 """
-from glob import glob
-from importlib import import_module
 import json
 import os
 import os.path
-from os.path import join as pjoin
 import re
 import shutil
 import sys
 import traceback
+from glob import glob
+from importlib import import_module
+from os.path import join as pjoin
 
 # This file is run as a script, and `import compat` is not zip-safe, so we
 # include write_json() and read_json() from compat.py.
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/build.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/build.py
index 2643014..9fecca2 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/build.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/build.py
@@ -3,13 +3,14 @@
 import argparse
 import logging
 import os
-from pip._vendor import toml
 import shutil
 
+from pip._vendor import toml
+
+from .compat import FileNotFoundError
+from .dirtools import tempdir, mkdir_p
 from .envbuild import BuildEnvironment
 from .wrappers import Pep517HookCaller
-from .dirtools import tempdir, mkdir_p
-from .compat import FileNotFoundError
 
 log = logging.getLogger(__name__)
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/check.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/check.py
index 13e722a..2c81f89 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/check.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/check.py
@@ -3,14 +3,15 @@
 import argparse
 import logging
 import os
-from os.path import isfile, join as pjoin
-from pip._vendor.toml import TomlDecodeError, load as toml_load
 import shutil
-from subprocess import CalledProcessError
 import sys
 import tarfile
-from tempfile import mkdtemp
 import zipfile
+from os.path import isfile, join as pjoin
+from subprocess import CalledProcessError
+from tempfile import mkdtemp
+
+from pip._vendor.toml import TomlDecodeError, load as toml_load
 
 from .colorlog import enable_colourful_output
 from .envbuild import BuildEnvironment
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/dirtools.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/dirtools.py
index 58c6ca0..5998643 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/dirtools.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/dirtools.py
@@ -1,9 +1,9 @@
-import os
-import io
 import contextlib
-import tempfile
-import shutil
 import errno
+import io
+import os
+import shutil
+import tempfile
 import zipfile
 
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/envbuild.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/envbuild.py
index 4088dcd..8a418ef 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/envbuild.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/envbuild.py
@@ -1,15 +1,16 @@
 """Build wheels/sdists by installing build deps to a temporary environment.
 """
 
-import os
 import logging
-from pip._vendor import toml
+import os
 import shutil
-from subprocess import check_call
 import sys
+from subprocess import check_call
 from sysconfig import get_paths
 from tempfile import mkdtemp
 
+from pip._vendor import toml
+
 from .wrappers import Pep517HookCaller, LoggerWrapper
 
 log = logging.getLogger(__name__)
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/meta.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/meta.py
index d525de5..5090d3e 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/meta.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/meta.py
@@ -1,10 +1,10 @@
 """Build metadata for a project using PEP 517 hooks.
 """
 import argparse
+import functools
 import logging
 import os
 import shutil
-import functools
 
 try:
     import importlib.metadata as imp_meta
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/wrappers.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/wrappers.py
index d6338ea..3ac69d0 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/wrappers.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/pep517/wrappers.py
@@ -1,10 +1,10 @@
+import os
+import shutil
+import sys
 import threading
 from contextlib import contextmanager
-import os
 from os.path import dirname, abspath, join as pjoin
-import shutil
 from subprocess import check_call, check_output, STDOUT
-import sys
 from tempfile import mkdtemp
 
 from . import compat
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/__init__.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/__init__.py
index 34a5eab..0ab1fba 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/__init__.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/__init__.py
@@ -3,8 +3,8 @@
 Released under the MIT license.
 """
 
-from pip._vendor.toml import encoder
 from pip._vendor.toml import decoder
+from pip._vendor.toml import encoder
 
 __version__ = "0.10.2"
 _spec_ = "0.5.0"
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/decoder.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/decoder.py
index e071100..1af1d2c 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/decoder.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/decoder.py
@@ -1,8 +1,8 @@
 import datetime
 import io
-from os import linesep
 import re
 import sys
+from os import linesep
 
 from pip._vendor.toml.tz import TomlTz
 
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/ordered.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/ordered.py
index 6052016..aaa4cc2 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/ordered.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/toml/ordered.py
@@ -1,6 +1,7 @@
 from collections import OrderedDict
-from pip._vendor.toml import TomlEncoder
+
 from pip._vendor.toml import TomlDecoder
+from pip._vendor.toml import TomlEncoder
 
 
 class TomlOrderedDecoder(TomlDecoder):
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/connection.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/connection.py
index f1e5d37..ad41bfc 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/connection.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/connection.py
@@ -4,9 +4,9 @@
 
 from pip._vendor.urllib3.exceptions import LocationParseError
 
+from .wait import NoWayToWaitForSocketError, wait_for_read
 from ..contrib import _appengine_environ
 from ..packages import six
-from .wait import NoWayToWaitForSocketError, wait_for_read
 
 
 def is_connection_dropped(conn):  # Platform-specific
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/ssl_.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/ssl_.py
index 763da82..358578e 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/ssl_.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/ssl_.py
@@ -7,6 +7,7 @@
 from binascii import hexlify, unhexlify
 from hashlib import md5, sha1, sha256
 
+from .url import BRACELESS_IPV6_ADDRZ_RE, IPV4_RE
 from ..exceptions import (
     InsecurePlatformWarning,
     ProxySchemeUnsupported,
@@ -14,7 +15,6 @@
     SSLError,
 )
 from ..packages import six
-from .url import BRACELESS_IPV6_ADDRZ_RE, IPV4_RE
 
 SSLContext = None
 SSLTransport = None
diff --git a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/timeout.py b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/timeout.py
index ff69593..96729be 100644
--- a/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/timeout.py
+++ b/backend/venv/lib/python3.9/site-packages/pip/_vendor/urllib3/util/timeout.py
@@ -1,7 +1,6 @@
 from __future__ import absolute_import
 
 import time
-
 # The default socket timeout, used by httplib to indicate that no timeout was
 # specified by the user
 from socket import _GLOBAL_DEFAULT_TIMEOUT