def update_upstream_port(self, port_name):
        if port_name in self.inputPorts:
            for connector in self.inputPorts[port_name]:
                connector.obj.update() # Might raise
            for connector in copy.copy(self.inputPorts[port_name]):
                if connector.obj.get_output(connector.port) is InvalidOutput:
                    self.remove_input_connector(port_name, connector)
Updates upstream of a single port instead of all ports.
dataset/ETHPy150Open VisTrails/VisTrails/vistrails/core/modules/vistrails_module.py/Module.update_upstream_port