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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 key_release_event(self, widget, event):
 """ Called when a key is released after being pressed. Adjust method signature as appropriate for callback. """

        # get keyname or keycode and translate to ginga standard
        # keyname =
        # keycode =
        keyname = ''  # self.transkey(keyname, keycode)
        self.logger.debug("key release event, key=%s" % (keyname))
        return self.make_ui_callback('key-release', keyname)