pep8analysis: remove old-style accessors in the AST

Note: the transformation was done with a script.
The parser cannot seem to be regenerated.
A future move could be to use nitcc instead.

Signed-off-by: Jean Privat <jean@pryen.org>
modelize_property: remove old-style accesors

Signed-off-by: Jean Privat <jean@pryen.org>