'Removes a port
Sends a port_status message to the controller
Returns the removed phy_port'

def delete_port(self, port):

    try:
        port_no = port.port_no
        assert (self.ports[port_no] is port)
    except:
        port_no = port
        port = self.ports[port_no]
    if (port_no not in self.ports):
        raise RuntimeError(("Can't    remove    nonexistent    port    " + str(port_no)))
    self.send_port_status(port, OFPPR_DELETE)
    del self.ports[port_no]
    return port
