rename billing date function to clearer about timezone

app/celery/tasks.py

@@ -487,7 +487,7 @@ def record_daily_sorted_counts(self, filename):
         )
         raise DVLAException(message)
 
-    billing_date = get_billing_date_in_est_from_filename(filename)
+    billing_date = get_local_billing_date_from_filename(filename)
     persist_daily_sorted_letter_counts(day=billing_date,
                                        file_name=filename,
                                        sorted_letter_counts=sorted_letter_counts)
@@ -503,7 +503,7 @@ def parse_dvla_file(filename):
         raise DVLAException('DVLA response file: {} has an invalid format'.format(filename))
 
 
-def get_billing_date_in_est_from_filename(filename):
+def get_local_billing_date_from_filename(filename):
     # exclude seconds from the date since we don't need it. We got a date ending in 60 second - which is not valid.
     datetime_string = filename.split('-')[1][:-2]
     datetime_obj = datetime.strptime(datetime_string, '%Y%m%d%H%M')

tests/app/celery/test_ftp_update_tasks.py

@@ -8,7 +8,7 @@ from freezegun import freeze_time
 
 from app.celery.tasks import (
     check_billable_units,
-    get_billing_date_in_est_from_filename,
+    get_local_billing_date_from_filename,
     persist_daily_sorted_letter_counts,
     process_updates_from_file,
     record_daily_sorted_counts,
@@ -236,9 +236,9 @@ def test_check_billable_units_when_billable_units_does_not_match_page_count(
     ('20170820000000', date(2017, 8, 19)),
     ('20170120230000', date(2017, 1, 20))
 ])
-def test_get_billing_date_in_est_from_filename(filename_date, billing_date):
+def test_get_local_billing_date_from_filename(filename_date, billing_date):
     filename = 'NOTIFY-{}-RSP.TXT'.format(filename_date)
-    result = get_billing_date_in_est_from_filename(filename)
+    result = get_local_billing_date_from_filename(filename)
 
     assert result == billing_date