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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_from_buffer(self, size=-1):
 """Remove at most size bytes from our buffer and return them."""

        # logger.debug('reading %r bytes from %r byte-long buffer', size, len(self._buffer))
        size = size if size >= 0 else len(self._buffer)
        part = self._buffer.read(size)
        self._current_pos += len(part)
        # logger.debug('part: %r', part)
        return part