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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def viewbox_mouse_event(self, event):
 """ The SubScene received a mouse event; update transform accordingly. Parameters event : instance of Event The event. """

        if event.handled or not self.interactive:
            return

        # Scrolling
        BaseCamera.viewbox_mouse_event(self, event)

        if event.type == 'mouse_wheel':
            center = self._scene_transform.imap(event.pos)
            self.zoom((1 + self.zoom_factor) ** (-event.delta[1] * 30), center)
            event.handled = True

        elif event.type == 'mouse_move':
            if event.press_event is None:
                return

            modifiers = event.mouse_event.modifiers
            p1 = event.mouse_event.press_event.pos
            p2 = event.mouse_event.pos

            if 1 in event.buttons and not modifiers:
                # Translate
                p1 = np.array(event.last_event.pos)[:2]
                p2 = np.array(event.pos)[:2]
                p1s = self._transform.imap(p1)
                p2s = self._transform.imap(p2)
                self.pan(p1s-p2s)
                event.handled = True
            elif 2 in event.buttons and not modifiers:
                # Zoom
                p1c = np.array(event.last_event.pos)[:2]
                p2c = np.array(event.pos)[:2]
                scale = ((1 + self.zoom_factor) **
                         ((p1c-p2c) * np.array([1, -1])))
                center = self._transform.imap(event.press_event.pos[:2])
                self.zoom(scale, center)
                event.handled = True
            else:
                event.handled = False
        elif event.type == 'mouse_press':
            # accept the event if it is button 1 or 2.
            # This is required in order to receive future events
            event.handled = event.button in [1, 2]
        else:
            event.handled = False