code: def detect_timezone():
    
    if sys.platform == "win32":
      tz = _detect_timezone_windows()
      if tz is not None:
        return tz
  
    # First we try the TZ variable
    tz = _detect_timezone_environ()
    if tz is not None:
      return tz
  
    # Second we try /etc/timezone and use the value in that
    tz = _detect_timezone_etc_timezone()
    if tz is not None:
      return tz
  
    # Next we try and see if something matches the tzinfo in /etc/localtime
    tz = _detect_timezone_etc_localtime()
    if tz is not None:
      return tz
  
    # Next we try and use a similiar method to what PHP does.
    # We first try to search on time.tzname, time.timezone, time.daylight to
    # match a pytz zone.
    warnings.warn("Had to fall back to worst detection method (the 'PHP' "
                  "method).")
  
    tz = _detect_timezone_php()
    if tz is not None:
      return tz
  
    raise pytz.UnknownTimeZoneError("Unable to detect your timezone!")
docs: Try and detect the timezone that Python is currently running in.
  
    We have a bunch of different methods for trying to figure this out (listed in
    order they are attempted).
      * In windows, use win32timezone.TimeZoneInfo.local()
      * Try TZ environment variable.
      * Try and find /etc/timezone file (with timezone name).
      * Try and find /etc/localtime file (with timezone data).
      * Try and match a TZ to the current dst/offset/shortname.
  
    Returns:
      The detected local timezone as a tzinfo object
  
    Raises:
      pytz.UnknownTimeZoneError: If it was unable to detect a timezone.