Fix flake8 linting
Fix flake8 linting

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