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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_verbosity_level(self, verbosity_level):
 """ Sets the Application verbosity level. :param verbosity_level: Verbosity level. :type verbosity_level: int :return: Method success. :rtype: bool :note: The expected verbosity level value is an integer between 0 to 4. """


        self.__verbosity_level = verbosity_level
        foundations.verbose.set_verbosity_level(verbosity_level)
        self.__settings.set_key("Settings", "verbosity_level", verbosity_level)
        self.verbosity_level_changed.emit(verbosity_level)
        return True