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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_datetime(time_str):
 """ Wraps dateutil's parser function to set an explicit UTC timezone, and to make sure microseconds are 0. Unified Uploader format and EMK format bother don't use microseconds at all. :param str time_str: The date/time str to parse. :rtype: datetime.datetime :returns: A parsed, UTC datetime. """

    try:
        return dateutil.parser.parse(
            time_str
        ).replace(microsecond=0).astimezone(UTC_TZINFO)
    except ValueError:
        # This was some kind of unrecognizable time string.
        raise ParseError("Invalid time string: %s" % time_str)