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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 set_shape(self, shape):
 """Update the shape."""

    channels = shape[-1]
    acceptable_channels = ACCEPTABLE_CHANNELS[self._encoding_format]
    if channels not in acceptable_channels:
      raise ValueError('Acceptable `channels` for %s: %s (was %s)' % (
          self._encoding_format, acceptable_channels, channels))
    self._shape = tuple(shape)