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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 returns(schema):
 """Create a decorator for validating function return value. Example:: @accepts(a=int, b=int) @returns(int) def f(a, b):
 return a + b :param schema: The schema for adapting a given parameter. """

    validate = parse(schema).validate

    @decorator
    def validating(func, *args, **kwargs):
        ret = func(*args, **kwargs)
        validate(ret, adapt=False)
        return ret
    return validating