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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_factory(schema, resolver=None, base_class=model.Model, name=None):
 """Generate a model class based on the provided JSON Schema :param schema: dict representing valid JSON schema :param name: A name to give the class, if `name` is not in `schema` """

    schema = copy.deepcopy(schema)
    resolver = resolver

    class Model(base_class):
        def __init__(self, *args, **kwargs):
            self.__dict__['schema'] = schema
            self.__dict__['resolver'] = resolver
            base_class.__init__(self, *args, **kwargs)

    if resolver is not None:
        Model.resolver = resolver

    if name is not None:
        Model.__name__ = name
    elif 'name' in schema:
        Model.__name__ = str(schema['name'])
    return Model