Revert "Merge pull request #13915 from edx/revert-13794-yro_implement-dateutil"

This reverts commit d59ab18b27, reversing
changes made to 0ebab35e89.

openedx/core/djangoapps/content/course_overviews/models.py

@@ -357,7 +357,6 @@ class CourseOverview(TimeStampedModel):
         """
         Returns True if the course starts with-in given number of days otherwise returns False.
         """
-
         return course_metadata_utils.course_starts_within(self.start, days)
 
     def start_datetime_text(self, format_string="SHORT_DATE", time_zone=utc):
@@ -389,6 +388,7 @@ class CourseOverview(TimeStampedModel):
     def end_datetime_text(self, format_string="SHORT_DATE", time_zone=utc):
         """
         Returns the end date or datetime for the course formatted as a string.
+
         """
         return course_metadata_utils.course_end_datetime_text(
             self.end,

openedx/core/lib/tests/test_time_zone_utils.py

@@ -1,12 +1,10 @@
 """Tests covering time zone utilities."""
 from freezegun import freeze_time
 from student.tests.factories import UserFactory
-from openedx.core.djangoapps.user_api.preferences.api import set_user_preference
 from openedx.core.lib.time_zone_utils import (
     get_display_time_zone,
     get_time_zone_abbr,
     get_time_zone_offset,
-    get_user_time_zone,
 )
 from pytz import timezone, utc
 from unittest import TestCase
@@ -25,20 +23,6 @@ class TestTimeZoneUtils(TestCase):
         self.user = UserFactory.build()
         self.user.save()
 
-    def test_get_user_time_zone(self):
-        """
-        Test to ensure get_user_time_zone() returns the correct time zone
-        or UTC if user has not specified time zone.
-        """
-        # User time zone should be UTC when no time zone has been chosen
-        user_tz = get_user_time_zone(self.user)
-        self.assertEqual(user_tz, utc)
-
-        # User time zone should change when user specifies time zone
-        set_user_preference(self.user, 'time_zone', 'Asia/Tokyo')
-        user_tz = get_user_time_zone(self.user)
-        self.assertEqual(user_tz, timezone('Asia/Tokyo'))
-
     def _display_time_zone_helper(self, time_zone_string):
         """
         Helper function to return all info from get_display_time_zone()

openedx/core/lib/time_zone_utils.py

@@ -2,19 +2,9 @@
 Utilities related to timezones
 """
 from datetime import datetime
-
 from pytz import common_timezones, timezone, utc
 
 
-def get_user_time_zone(user):
-    """
-    Returns pytz time zone object of the user's time zone if available or UTC time zone if unavailable
-    """
-    #TODO: exception for unknown timezones?
-    time_zone = user.preferences.model.get_value(user, "time_zone", 'utc')
-    return timezone(time_zone)
-
-
 def _format_time_zone_string(time_zone, date_time, format_string):
     """
     Returns a string, specified by format string, of the current date/time of the time zone.