Good catch Martin. Indeed, "pass", "break" and "continue" don't need a space, and "True", "False" and "None" need a space only in rare cases like "None in collection". Some keywords ("else", "finally", "try") need a colon. But while "return" and "lambda" not always need a space, I think that needing a space is more common case, and in any case the redundant space doesn't make a harm.

Here is revised patch that doesn't add a space in some cases and instead adds a colon in some cases.