pyqt_signals.py

from PyQt4 import Qt

def Signal(name, *args):
    def get_signal(self):
        if not hasattr(self, '_signallers'):
            self._signallers = {}
        if (name, args) not in self._signallers:
            signal = Qt.pyqtSignal(*args, name=name)
            signaller_type = type('Signaller', (Qt.QObject,), {name: signal})
            self._signallers[name, args] = signaller_type()
        signaller = self._signallers[name, args]
        return getattr(signaller, name)
    return property(get_signal)

class Base(object):
    test = Signal('test', int)

class MyWidget(Qt.QLabel, Base):
    def __init__(self):
        Qt.QLabel.__init__(self, 'testing signal')
        self.test.connect(self.onSignal)
        self.test.emit(3)

    def onSignal(self, arg):
        print "Got:", arg

app=Qt.QApplication([])
w = MyWidget()
w.show()
app.exec_()