revert breaking changes!

evap/staff/views.py

@@ -1,4 +1,3 @@
-import codecs
 import csv
 import itertools
 from collections import OrderedDict, defaultdict, namedtuple
@@ -2130,6 +2129,7 @@ def user_export(request):
     writer.writerows(
         (user.title, user.last_name, user.first_name, user.email) for user in UserProfile.objects.iterator()
     )
+    return response
 
 
 @manager_required

tools/enrollment_preprocessor.py

@@ -74,7 +74,7 @@ def run_preprocessor(enrollment_data: str | BytesIO, user_data: TextIO) -> Bytes
             fix_user(users, UserCells(*wb_row[7:]))
     wb_out = BytesIO()
     workbook.save(wb_out)
-    wb.seek(0)
+    wb_out.seek(0)
     return wb_out
 
 
@@ -83,7 +83,7 @@ def run_preprocessor(enrollment_data: str | BytesIO, user_data: TextIO) -> Bytes
     parser.add_argument("user-data", help="Path to a csv file containing an export of all existing users.")
     parser.add_argument("enrollment-data", help="Path to the enrollment data in xlsx format for import.")
     ns = parser.parse_args()
-    with open(ns.user_data) as csvfile:
+    with open(ns.user_data, encoding="utf-8") as csvfile:
         wb = run_preprocessor(ns.enrollment_data, csvfile)
     with open(ns.enrollment_data, "wb") as out:
         out.write(wb.read())