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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 search_function(cls, encoding):
 """Search function to find 'rotunicode' codec."""

        if encoding == cls._codec_name:
            return codecs.CodecInfo(
                name=cls._codec_name,
                encode=cls.encode,
                decode=cls.decode,
            )
        return None