def time2internaldate(date_time):
    """Convert date_time to IMAP4 INTERNALDATE representation.

    Return string in form: '"DD-Mmm-YYYY HH:MM:SS +HHMM"'.  The
    date_time argument can be a number (int or float) representing
    seconds since epoch (as returned by time.time()), a 9-tuple
    representing local time, an instance of time.struct_time (as
    returned by time.localtime()), an aware datetime instance or a
    double-quoted string.  In the last case, it is assumed to already
    be in the correct format.
    """
    if isinstance(date_time, (int, float)):
        dt = datetime.fromtimestamp(date_time, timezone.utc).astimezone()
    elif isinstance(date_time, tuple):
        try:
            gmtoff = date_time.tm_gmtoff
        except AttributeError:
            if time.daylight:
                dst = date_time[8]
                if dst == -1:
                    dst = time.localtime(time.mktime(date_time))[8]
                gmtoff = -(time.timezone, time.altzone)[dst]
            else:
                gmtoff = -time.timezone
        delta = timedelta(seconds=gmtoff)
        dt = datetime(*date_time[:6], tzinfo=timezone(delta))
    elif isinstance(date_time, datetime):
        if date_time.tzinfo is None:
            raise ValueError("date_time must be aware")
        dt = date_time
    elif isinstance(date_time, str) and (date_time[0],date_time[-1]) == ('"','"'):
        return date_time        # Assume in correct format
    else:
        raise ValueError("date_time not of a known type")
    fmt = '"%d-{}-%Y %H:%M:%S %z"'.format(Months[dt.month])
    return dt.strftime(fmt)
Convert date_time to IMAP4 INTERNALDATE representation.

    Return string in form: '"DD-Mmm-YYYY HH:MM:SS +HHMM"'.  The
    date_time argument can be a number (int or float) representing
    seconds since epoch (as returned by time.time()), a 9-tuple
    representing local time, an instance of time.struct_time (as
    returned by time.localtime()), an aware datetime instance or a
    double-quoted string.  In the last case, it is assumed to already
    be in the correct format.