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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 append(self, data, size):
 """ Append user-supplied data to chunk, return resulting chunk size. If the data would exceeded the available space, it is truncated. If you want to grow the chunk to accommodate new data, use the zchunk_extend method. """

        return lib.zchunk_append(self._as_parameter_, data, size)