Updated type of source in compile() from Any

[ashwch]

Python 2:

source can either be a Unicode string, a Latin-1 encoded string or an AST object.

Python 3:

source can either be a normal string, a byte string, or an AST object.

[gvanrossum]

Hm... The mypy test failures seem to be due to 3f9fafb (#1515). This would seem strange, but I think it is due to the addition of a dependency from builtins on ast (and implicitly on _ast). The builtins module and a small number of others are part of an import cycle that is always imported (because everything depends on builtins), and within this import cycle, strange things happen because it's part of bootstrapping the basic types.

Alas, I don't know how to fix this -- but I think it's wise to just close this rather than to try and worry too much about it.

[ashwch]

Ouch! :-(