Fixed #17882 -- Reopened the database connection when a test changes time zone...

from django.conf import settings

from django.db import close_connection

from django.dispatch import Signal

template_rendered = Signal(providing_args=["template", "context"])

setting_changed = Signal(providing_args=["setting", "value"])

# Close the database connection to re-establish it with the proper time zone.

def close_connection_on_time_zone_change(**kwargs):

    if (kwargs['setting'] == 'USE_TZ'

        or (kwargs['setting'] == 'TIME_ZONE' and not settings.USE_TZ)):

        close_connection()

setting_changed.connect(close_connection_on_time_zone_change)

            self._old_tz = os.environ.get('TZ')

            os.environ['TZ'] = 'Africa/Nairobi'

            time.tzset()

        # Create a new cursor, for test cases that change the value of USE_TZ.

        connection.close()

    @classmethod

    def tearDownClass(self):