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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 model_import(self):
 """ Import and instantiate the non-JIT models and the JIT models. Models defined in ``jits`` and ``non_jits`` in ``models/__init__.py`` will be imported and instantiated accordingly. Returns ------- None """

        # non-JIT models
        for file, pair in non_jits.items():
            for cls, name in pair.items():
                themodel = importlib.import_module('andes.models.' + file)
                theclass = getattr(themodel, cls)
                self.__dict__[name] = theclass(self, name)

                group = self.__dict__[name]._group
                self.group_add(group)
                self.__dict__[group].register_model(name)

                self.devman.register_device(name)

        # import JIT models
        for file, pair in jits.items():
            for cls, name in pair.items():
                self.__dict__[name] = JIT(self, file, cls, name)