def METHOD_NAME(tzenv):
    if tzenv[0] == ':':
        tzenv = tzenv[1:]
    # TZ specifies a file
    if os.path.exists(tzenv):
        with open(tzenv, 'rb') as tzfile:
            return pytz.tzfile.build_tzinfo('local', tzfile)
    # TZ specifies a zoneinfo zone.
    try:
        tz = pytz.timezone(tzenv)
        # That worked, so we return this:
        return tz
    except pytz.UnknownTimeZoneError:
        raise pytz.UnknownTimeZoneError(
            "tzlocal() does not support non-zoneinfo timezones like %s. \n"
            "Please use a timezone in the form of Continent/City")