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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_encoding_format(self, encoding_format):
 """Update the encoding format."""

    supported = ENCODE_FN.keys()
    if encoding_format not in supported:
      raise ValueError('`encoding_format` must be one of %s.' % supported)
    self._encoding_format = encoding_format