* Remove the slice type.
* Make Slice a kind of the expr type instead of the slice type.
* Replace ExtSlice(slices) with Tuple(slices, Load()).
* Replace Index(value) with a value itself.
All non-terminal nodes in AST for expressions are now of the expr type.
The fix changes copy_location() to require an extra node from which to extract the end location, and fixing all 5 call sites.
https://bugs.python.org/issue39235
When parsing an "elif" node, lineno and col_offset of the node now point to the "elif" keyword and not to its condition, making it consistent with the "if" node.
https://bugs.python.org/issue39031
Automerge-Triggered-By: @pablogsal
All call sites pass NULL for `recode_encoding`, so this path is
completely untested. That's been true since before Python 3.0.
It adds significant complexity to this logic, so it's best to
take it out.
All call sites now have a literal NULL, and that's been true since
commit 768921cf3 eliminated a conditional (`foo ? bar : NULL`) at
the call site in Python/ast.c where we're parsing a bytes literal.
But even before then, that condition `foo` had been a constant
since unadorned string literals started meaning Unicode, in commit
572dbf8f1 aka v3.0a1~1035 .
The `unicode` parameter is already unused, so mark it as unused too.
The code that acted on it was also taken out before Python 3.0, in
commit 8d30cc014 aka v3.0a1~1031 .
The function (PyBytes_DecodeEscape) is exposed in the API, but it's
never been documented.
