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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 _time_query_parms(begin_time, end_time):
 """Return the URI query paramterer string for the specified begin time and end time."""

        query_parms = []
        if begin_time is not None:
            begin_ts = timestamp_from_datetime(begin_time)
            qp = 'begin-time={}'.format(begin_ts)
            query_parms.append(qp)
        if end_time is not None:
            end_ts = timestamp_from_datetime(end_time)
            qp = 'end-time={}'.format(end_ts)
            query_parms.append(qp)
        query_parms_str = '&'.join(query_parms)
        if query_parms_str:
            query_parms_str = '?' + query_parms_str
        return query_parms_str