" remove in 2.0
if exists('g:ale_python_flake8_args') && !s:deprecation_warning_echoed
execute 'echom ''Rename your g:ale_python_flake8_args setting to g:ale_python_flake8_options instead. Support for this will removed in ALE 2.0.'''
let s:deprecation_warning_echoed = 1
endif
参考ale的commit,目前syntastic_python_flake8_args已经失效
https://github.com/w0rp/ale/commit/191967cfeec78f3ba83d999462fe6e45e4f4c8de#diff-89fcb160c54b00efbfe4cde9e743ca22