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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 _NormalizeDuration(self, seconds, nanos):
 """Set Duration by seconds and nonas."""

    # Force nanos to be negative if the duration is negative.
    if seconds < 0 and nanos > 0:
      seconds += 1
      nanos -= _NANOS_PER_SECOND
    self.seconds = seconds
    self.nanos = nanos