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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 _xorterm_prime(lexer):
 """Return an xor term' expression, eliminates left recursion."""

    tok = next(lexer)
    # '^' PRODTERM XORTERM'
    if isinstance(tok, OP_xor):
        prodterm = _prodterm(lexer)
        xorterm_prime = _xorterm_prime(lexer)
        if xorterm_prime is None:
            return prodterm
        else:
            return ('xor', prodterm, xorterm_prime)
    # null
    else:
        lexer.unpop_token(tok)
        return None