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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 date_to_milliseconds(date_str):
 """Convert UTC date to milliseconds If using offset strings add "UTC" to date string e.g. "now UTC", "11 hours ago UTC" See dateparse docs for formats http://dateparser.readthedocs.io/en/latest/ :param date_str: date in readable format, i.e. "January 01, 2018", "11 hours ago UTC", "now UTC" :type date_str: str """

    # get epoch value in UTC
    epoch = datetime.utcfromtimestamp(0).replace(tzinfo=pytz.utc)
    # parse our date string
    d = dateparser.parse(date_str)
    # if the date is not timezone aware apply UTC timezone
    if d.tzinfo is None or d.tzinfo.utcoffset(d) is None:
        d = d.replace(tzinfo=pytz.utc)

    # return the difference in time
    return int((d - epoch).total_seconds() * 1000.0)