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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 parse_human_datetime(s):
 """ Returns ``datetime.datetime`` from human readable strings datetime.datetime(2015, 4, 3, 0, 0) datetime.datetime(1969, 2, 3, 0, 0) True True True True """

    if not s:
        return None
    try:
        dttm = parse(s)
    except Exception:
        try:
            cal = parsedatetime.Calendar()
            parsed_dttm, parsed_flags = cal.parseDT(s)
            # when time is not extracted, we 'reset to midnight'
            if parsed_flags & 2 == 0:
                parsed_dttm = parsed_dttm.replace(hour=0, minute=0, second=0)
            dttm = dttm_from_timtuple(parsed_dttm.utctimetuple())
        except Exception as e:
            logging.exception(e)
            raise ValueError("Couldn't parse date string [{}]".format(s))
    return dttm