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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 write_multi(self, frames, encoded_frames=None):
 """Writes multiple video frames."""

    if encoded_frames is None:
      # Infinite iterator.
      encoded_frames = iter(lambda: None, 1)
    for (frame, encoded_frame) in zip(frames, encoded_frames):
      self.write(frame, encoded_frame)