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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 check_length(value, length):
 """ Checks length of value @param value: value to check @type value: C{str} @param length: length checking for @type length: C{int} @return: None when check successful @raise ValueError: check failed """

    _length = len(value)
    if _length != length:
        raise ValueError("length must be %d, not %d" % \
                         (length, _length))