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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 read(self, size=-1):
 """Read data from the ring buffer into a new buffer. This advances the read index after reading; calling :meth:`advance_read_index` is *not* necessary. :param size: The number of elements to be read. If not specified, all available elements are read. :type size: int, optional :returns: A new buffer containing the read data. Its size may be less than the requested *size*. :rtype: buffer """

        if size < 0:
            size = self.read_available
        data = self._ffi.new('unsigned char[]', size * self.elementsize)
        size = self.readinto(data)
        return self._ffi.buffer(data, size * self.elementsize)