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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 _NormalizeTime(self, time):
 """Normalize a time to be an int measured in microseconds."""

    if isinstance(time, rdfvalue.RDFDatetime):
      return time.AsMicrosecondsSinceEpoch()
    if isinstance(time, rdfvalue.Duration):
      return time.microseconds
    return int(time)