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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 import_model(cls, ins_name):
 """Import model class in models package """

        try:
            package_space = getattr(cls, 'package_space')
        except AttributeError:
            raise ValueError('package_space not exist')
        else:
            return import_object(ins_name, package_space)