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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 group_add(self, name='Ungrouped'):
 """ Dynamically add a group instance to the system if not exist. Parameters name : str, optional ('Ungrouped' as default) Name of the group Returns ------- None """

        if not hasattr(self, name):
            self.__dict__[name] = Group(self, name)
            self.loaded_groups.append(name)