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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 positive_value(target_type):
 """ Wraps target_type in a function that requires the parsed argument be >= 0 """

    def inner(string):
        value = target_type(string)
        if not value >= 0:
            raise argparse.ArgumentTypeError("Invalid positive number: " +
                    string)
        return value

    return inner