> Disagree. The original commenter is correct in saying that the naming scheme is not obvious. Something like to_bytes(encoding) would be a lot more clear.

But then function would do something completely different. "\x01\x02".encode('zlib') for instance is a bytes to bytes operation. The problem is that "foo".encode('utf-8') does not give you an exception. If the coercion would not be enabled you would get an error:

    >>> reload(sys).setdefaultencoding('undefined')
    >>> 'foo'.encode('utf-8')
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "/usr/local/Cellar/python/.../encodings/undefined.py", line 22, in decode
        raise UnicodeError("undefined encoding")
    UnicodeError: undefined encoding

That's not any worse than what Python 3 does:

    >>> b'foo'.encode('utf-8')
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: 'bytes' object has no attribute 'encode'

> "\x01\x02".encode('zlib') for instance is a bytes to bytes operation.

I think the inclusion of things like zlib (or rot13 or whatever) was a conceptual error that just fosters confusion.

The principle of least astonishment and optimizing for idiocy are not the same thing.

How is an attribute error clearer than an exception that says something like: operation does not make sense of this type?

"\x01\x02".encode('zlib') is a really odd API. Just making sure: this is a real thing, and you're in favor of it?

It is in Python 2, but not in Python 3, where str.encode() and bytes.decode() have been restricted to only convert between strings and bytes.

    >>> "foo".encode('zlib')
    LookupError: 'zlib' is not a text encoding; use codecs.encode() to handle arbitrary codecs

> "\x01\x02".encode('zlib') is a really odd API. Just making sure: this is a real thing, and you're in favor of it?

Of course this is a real thing and it's very frequently used. Yes I am in favour of it as the codec system in Python is precisely the place where things like this should live.