Add flake8 config

Co-authored-by: pokemon918 <132939190+pokemon918@users.noreply.github.com>
Co-authored-by: xfactor-toml <154992305+xfactor-toml@users.noreply.github.com>
Co-authored-by: omni-omega <234262665+omni-omega@users.noreply.github.com>
Co-authored-by: phantomdev0826 <218786589+phantomdev0826@users.noreply.github.com>

Author: 5 people

.flake8

@@ -0,0 +1 @@
+[flake8]\nmax-line-length = 120\nexclude =\n    .git,\n    __pycache__,\n    venv,\n    .eggs,\n    build\nignore = E203, W503