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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 set_checked(self, state):
 """ Sets the Widget checked state. :param state: New check state. :type state: bool :return: Method success. :rtype: bool """


        if not self.__checkable:
            return False

        if state:
            self.__checked = True
            self.setPixmap(self.__active_pixmap)
        else:
            self.__checked = False
            self.setPixmap(self.__default_pixmap)
        self.toggled.emit(state)
        return True