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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 readinto(self, data):
 """Read data from the ring buffer into a user-provided buffer. This advances the read index after reading; calling :meth:`advance_read_index` is *not* necessary. :param data: The memory where the data should be stored. :type data: CData pointer or buffer :returns: The number of elements read, which may be less than the size of *data*. :rtype: int """

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