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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 _controller_buffer(self, port):
 """ Find the pointer to a controller and setup a NumPy buffer. Args: port: the port of the controller to setup Returns: a NumPy buffer with the controller's binary data """

        # get the address of the controller
        address = _LIB.Controller(self._env, port)
        # create a memory buffer using the ctypes pointer for this vector
        buffer_ = ctypes.cast(address, ctypes.POINTER(CONTROLLER_VECTOR)).contents
        # create a NumPy buffer from the binary data and return it
        return np.frombuffer(buffer_, dtype='uint8')