Ensure we always run flake8-bugbear

This assumes that we no longer use Python 2.7 for running the flake8
tests any more.

stdnum/cz/bankaccount.py

@@ -83,7 +83,7 @@ def _info(bank):
     """Look up information for the bank."""
     from stdnum import numdb
     info = {}
-    for nr, found in numdb.get('cz/banks').info(bank):
+    for _nr, found in numdb.get('cz/banks').info(bank):
         info.update(found)
     return info
 

stdnum/nz/bankaccount.py

@@ -104,7 +104,7 @@ def info(number):
     number = compact(number)
     from stdnum import numdb
     info = {}
-    for nr, found in numdb.get('nz/banks').info(number):
+    for _nr, found in numdb.get('nz/banks').info(number):
         info.update(found)
     return info
 

tox.ini

@@ -16,7 +16,7 @@ skip_install = true
 deps = flake8
        flake8-author
        flake8-blind-except
-       py{35,36,37,38}: flake8-bugbear
+       flake8-bugbear
        flake8-class-newline
        flake8-commas
        flake8-deprecated

update/iban.py

@@ -57,7 +57,7 @@ def get_country_codes(line):
             for i, c in enumerate(row[1:]):
                 values[i][row[0]] = c
     # output the collected data
-    for i, data in values.items():
+    for _i, data in values.items():
         bban = data['BBAN structure']
         if not bban or bban.lower() == 'n/a':
             bban = data['IBAN structure']