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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 is_shortcut_in_use(self, shortcut):
 """ Returns if given action shortcut is in use. :param name: Action shortcut. :type name: unicode :return: Is shortcut in use. :rtype: bool """


        for path, actionName, action in foundations.walkers.dictionaries_walker(self.__categories):
            if action.shortcut() == QKeySequence(shortcut):
                return True
        return False