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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(self, data, size=-1):
 """Write data to the ring buffer. This advances the write index after writing; calling :meth:`advance_write_index` is *not* necessary. :param data: Data to write to the buffer. :type data: CData pointer or buffer or bytes :param size: The number of elements to be written. :type size: int, optional :returns: The number of elements written. :rtype: int """

        try:
            data = self._ffi.from_buffer(data)
        except TypeError:
            pass  # input is not a buffer
        if size < 0:
            size, rest = divmod(self._ffi.sizeof(data), self.elementsize)
            if rest:
                raise ValueError('data size must be multiple of elementsize')
        return self._lib.PaUtil_WriteRingBuffer(self._ptr, data, size)