Pyxhook源代码中对Python类的困惑

Question

我目前正在使用Python中的一个库来记录所有用户输入。源代码可以在这里找到：https://github.com/JeffHoogland/pyxhook/blob/master/pyxhook.py

我已经看了一段时间的源代码，但无法弄清楚它是如何工作的。我在整个源代码中跟踪了函数processevents(self, reply)，并且不了解vairble event的来源。确切的行是：

def processevents(self, reply):
        if reply.category != record.FromServer:
            return
        if reply.client_swapped:
            print("* received swapped protocol data, cowardly ignored")
            return
        try:
            # Get int value, python2.
            intval = ord(reply.data[0])
        except TypeError:
            # Already bytes/ints, python3.
            intval = reply.data[0]
        if (not reply.data) or (intval < 2):
            # not an event
            return
        data = reply.data
        while len(data):
            event, data = rq.EventField(None).parse_binary_value(
                data,
                self.record_dpy.display,
                None,
                None
            )
            if event.type == X.KeyPress:
                hookevent = self.keypressevent(event)
                self.KeyDown(hookevent)
            elif event.type == X.KeyRelease:
                hookevent = self.keyreleaseevent(event)
                self.KeyUp(hookevent)
            elif event.type == X.ButtonPress:
                hookevent = self.buttonpressevent(event)
                self.MouseAllButtonsDown(hookevent)
            elif event.type == X.ButtonRelease:
                hookevent = self.buttonreleaseevent(event)
                self.MouseAllButtonsUp(hookevent)
            elif event.type == X.MotionNotify:
                # use mouse moves to record mouse position, since press and
                # release events do not give mouse position info
                # (event.root_x and event.root_y have bogus info).
                hookevent = self.mousemoveevent(event)
                self.MouseMovement(hookevent)

        # print("processing events...", event.type)