r"""Retrieves a descriptor from the device identified by the type
        and index of the descriptor.

        Arguments:
            desc_type: descriptor type.
            desc_index: index of the descriptor.
            len: descriptor length.
            endpoint: ignored.

def getDescriptor(self, desc_type, desc_index, length, endpoint = -1):
        r"""Retrieves a descriptor from the device identified by the type
        and index of the descriptor.

        Arguments:
            desc_type: descriptor type.
            desc_index: index of the descriptor.
            len: descriptor length.
            endpoint: ignored.
        """
        return control.get_descriptor(self.dev, length, desc_type, desc_index)