[Python] Auto-complete not working on lines starting with `return`

### Expected behavior When typing on a line starting with `return` the auto-complete should work. ### Actual behavior When tying on a line starting with return auto-complete is non-functional. This was introduced by 41c1f3a931fdc4e7de979888e67d37851e2291c0. This would also break auto-complete on lines starting with `break|continue|pass`, when typing a comment after them. ### Steps to reproduce Type the following: ``` def foo(): return f ``` The auto-complete should suggest `foo`, but pressing *enter* just enters a newline.