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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_cache_time_left(expires_header):
 """ return the time left in second for an expires header """

    epoch = datetime(1970, 1, 1)
    # this date is ALWAYS in UTC (RFC 7231)
    expire = (
        datetime(
            *parsedate(expires_header)[:6]
        ) - epoch
    ).total_seconds()
    now = (datetime.utcnow() - epoch).total_seconds()
    return int(expire) - int(now)