def obfuscate_unique(tokens, index, replace, replacement, *args):
    """
    If the token string (a unique value anywhere) inside *tokens[index]*
    matches *replace*, return *replacement*.

    .. note::

        This function is only for replacing absolutely unique ocurrences of
        *replace* (where we don't have to worry about their position).
    """
    def return_replacement(replacement):
        UNIQUE_REPLACEMENTS[replacement] = replace
        return replacement
    tok = tokens[index]
    token_type = tok[0]
    token_string = tok[1]
    if token_type != tokenize.NAME:
        return None # Skip this token
    if token_string == replace:
        return return_replacement(replacement)
If the token string (a unique value anywhere) inside *tokens[index]*
    matches *replace*, return *replacement*.

    .. note::

        This function is only for replacing absolutely unique ocurrences of
        *replace* (where we don't have to worry about their position).