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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 require_request_model(cls, validate=True):
 """ Makes a handler require that a request body that map towards the given model is provided. Unless the ``validate`` option is set to ``False`` the data will be validated against the model's fields. The model will be passed to the handler as the last positional argument. :: @require_request_model(Model) async def handle_model(request, model):
 return 200, model """

    def decorator(handler):
        async def new_handler(request, *args, **kwargs):
            body = await request.json()
            model = cls(**body)

            if validate:
                model.validate()

            return await handler(request, model, *args, **kwargs)
        return new_handler
    return decorator