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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 _handle_mouse(self, ev):
 """ Handle mouse events. Return a list of KeyPress instances. """

        FROM_LEFT_1ST_BUTTON_PRESSED = 0x1

        result = []

        # Check event type.
        if ev.ButtonState == FROM_LEFT_1ST_BUTTON_PRESSED:
            # On a key press, generate both the mouse down and up event.
            for event_type in [MouseEventType.MOUSE_DOWN, MouseEventType.MOUSE_UP]:
                data = ';'.join([
                   event_type,
                   str(ev.MousePosition.X),
                   str(ev.MousePosition.Y)
                ])
                result.append(KeyPress(Keys.WindowsMouseEvent, data))

        return result