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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 norm_join(prefix, suffix):
 """ Join ``prefix`` and ``suffix`` paths and return the resulting path, normalized. :param string prefix: the prefix path :param string suffix: the suffix path :rtype: string """

    if (prefix is None) and (suffix is None):
        return "."
    if prefix is None:
        return os.path.normpath(suffix)
    if suffix is None:
        return os.path.normpath(prefix)
    return os.path.normpath(os.path.join(prefix, suffix))