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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=None):
 # pylint: disable=missing-docstring """Read at most size bytes from this slice. Compared to other streams, there is one case where we may unexpectedly raise an exception on read: if the underlying stream is exhausted (i.e. returns no bytes on read), and the size of this slice indicates we should still be able to read more bytes, we raise exceptions.StreamExhausted. Args: size: If provided, read no more than size bytes from the stream. Returns: The bytes read from this slice. Raises: exceptions.StreamExhausted """

        if size is not None:
            read_size = min(size, self.__remaining_bytes)
        else:
            read_size = self.__remaining_bytes
        data = self.__stream.read(read_size)
        if read_size > 0 and not data:
            raise exceptions.StreamExhausted(
                'Not enough bytes in stream; expected %d, exhausted '
                'after %d' % (
                    self.__max_bytes,
                    self.__max_bytes - self.__remaining_bytes))
        self.__remaining_bytes -= len(data)
        return data