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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 length(value, min=None, max=None):
 """ Return whether or not the length of given string is within a specified range. Examples:: True True :param value: The string to validate. :param min: The minimum required length of the string. If not provided, minimum length will not be checked. :param max: The maximum length of the string. If not provided, maximum length will not be checked. .. versionadded:: 0.2 """

    if (min is not None and min < 0) or (max is not None and max < 0):
        raise AssertionError(
            '`min` and `max` need to be greater than zero.'
        )
    return between(len(value), min=min, max=max)