fix flake linting issue
fix flake linting issue

cjh1/tomviz,cryos/tomviz,thewtex/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,cjh1/tomviz,OpenChemistry/tomviz,thewtex/tomviz,mathturtle/tomviz,cjh1/tomviz,cryos/tomviz,mathturtle/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz,thewtex/tomviz,cryos/tomviz