django-mssql / sqlserver_ado /

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TZ helper functions backported from Django 1.4. This module should only 
get loaded if django.utils.timezone doesn't exist.
from datetime import timedelta, tzinfo

    import pytz
except ImportError:
    pytz = None

__all__ = [
    'utc', 'is_aware'

# UTC and local time zones

ZERO = timedelta(0)

class UTC(tzinfo):
    UTC implementation taken from Python's docs.

    Used only when pytz isn't available.

    def __repr__(self):
        return "<UTC>"

    def utcoffset(self, dt):
        return ZERO

    def tzname(self, dt):
        return "UTC"

    def dst(self, dt):
        return ZERO

utc = pytz.utc if pytz else UTC()
"""UTC time zone as a tzinfo instance."""

def is_aware(value):
    Determines if a given datetime.datetime is aware.

    The logic is described in Python's docs:
    return value.tzinfo is not None and value.tzinfo.utcoffset(value) is not None