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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 _MakeTimestamp(self, start=None, end=None):
 """Create a timestamp using a start and end time. Args: start: Start timestamp. end: End timestamp. Returns: A tuple (start, end) of converted timestamps or None for all time. """

    mysql_unsigned_bigint_max = 18446744073709551615
    ts_start = int(start or 0)
    if end is None:
      ts_end = mysql_unsigned_bigint_max
    else:
      ts_end = int(end)
    if ts_start == 0 and ts_end == mysql_unsigned_bigint_max:
      return None
    else:
      return (ts_start, ts_end)