closes bpo-31902: Fix the col_offset attribute for ast.Async* nodes to point to the "async" keyword. (GH-4175)


Previously, col_offset points to the keyword after "async".
(cherry picked from commit 90fc8980bbcc5c7dcced3627fe172b0bfd193a3b)

Co-authored-by: guoci <zguoci@gmail.com>
3 files changed