Transform tokens back into Python source code.
    It returns a bytes object, encoded using the ENCODING
    token, which is the first token sequence output by tokenize.

    Each element returned by the iterable must be a token sequence
    with at least two elements, a token number and token value.  If
    only two tokens are passed, the resulting output is poor.

    Round-trip invariant for full input:
        Untokenized source will match input source exactly

    Round-trip invariant for limited input:
        # Output bytes will tokenize back to the input
        t1 = [tok[:2] for tok in tokenize(f.readline)]
        newcode = untokenize(t1)
        readline = BytesIO(newcode).readline
        t2 = [tok[:2] for tok in tokenize(readline)]
        assert t1 == t2

def untokenize(iterable):
    """Transform tokens back into Python source code.
    It returns a bytes object, encoded using the ENCODING
    token, which is the first token sequence output by tokenize.

    Each element returned by the iterable must be a token sequence
    with at least two elements, a token number and token value.  If
    only two tokens are passed, the resulting output is poor.

    Round-trip invariant for full input:
        Untokenized source will match input source exactly

    Round-trip invariant for limited input:
        # Output bytes will tokenize back to the input
        t1 = [tok[:2] for tok in tokenize(f.readline)]
        newcode = untokenize(t1)
        readline = BytesIO(newcode).readline
        t2 = [tok[:2] for tok in tokenize(readline)]
        assert t1 == t2
    """
    ut = Untokenizer()
    out = ut.untokenize(iterable)
    if ut.encoding is not None:
        out = out.encode(ut.encoding)
    return out