Update algorithms/operators/product.py to be PEP8 complaint
Update algorithms/operators/product.py to be PEP8 complaint

dmoliveira/networkx,kernc/networkx,ghdk/networkx,ghdk/networkx,farhaanbukhsh/networkx,harlowja/networkx,RMKD/networkx,aureooms/networkx,wasade/networkx,sharifulgeo/networkx,michaelpacer/networkx,bzero/networkx,chrisnatali/networkx,cmtm/networkx,dmoliveira/networkx,ionanrozenfeld/networkx,nathania/networkx,farhaanbukhsh/networkx,aureooms/networkx,sharifulgeo/networkx,JamesClough/networkx,blublud/networkx,dhimmel/networkx,kernc/networkx,yashu-seth/networkx,sharifulgeo/networkx,OrkoHunter/networkx,kernc/networkx,nathania/networkx,NvanAdrichem/networkx,harlowja/networkx,jcurbelo/networkx,jakevdp/networkx,jfinkels/networkx,chrisnatali/networkx,nathania/networkx,tmilicic/networkx,blublud/networkx,ionanrozenfeld/networkx,ltiao/networkx,RMKD/networkx,dhimmel/networkx,jakevdp/networkx,aureooms/networkx,dmoliveira/networkx,farhaanbukhsh/networkx,bzero/networkx,debsankha/networkx,debsankha/networkx,SanketDG/networkx,blublud/networkx,andnovar/networkx,goulu/networkx,debsankha/networkx,harlowja/networkx,chrisnatali/networkx,RMKD/networkx,beni55/networkx,ionanrozenfeld/networkx,ghdk/networkx,dhimmel/networkx,bzero/networkx,jakevdp/networkx,Sixshaman/networkx