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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 register_system_role(self, system_role):
 """Register a system role. .. note:: A system role can't be registered two times. If it happens, then an assert exception will be raised. :param system_role: The system role to be registered. """

        assert system_role.value not in self.system_roles
        self.system_roles[system_role.value] = system_role