Added test for _print_Mul() method.
Added test for _print_Mul() method.

asm666/sympy,Sumith1896/sympy,amitjamadagni/sympy,saurabhjn76/sympy,Titan-C/sympy,debugger22/sympy,iamutkarshtiwari/sympy,sunny94/temp,sunny94/temp,ChristinaZografou/sympy,jerli/sympy,drufat/sympy,liangjiaxing/sympy,yukoba/sympy,kaichogami/sympy,Sumith1896/sympy,pandeyadarsh/sympy,kaichogami/sympy,drufat/sympy,toolforger/sympy,grevutiu-gabriel/sympy,aktech/sympy,oliverlee/sympy,beni55/sympy,wanglongqi/sympy,rahuldan/sympy,ga7g08/sympy,mcdaniel67/sympy,sahilshekhawat/sympy,dqnykamp/sympy,farhaanbukhsh/sympy,Arafatk/sympy,postvakje/sympy,Titan-C/sympy,dqnykamp/sympy,sampadsaha5/sympy,shipci/sympy,abloomston/sympy,Titan-C/sympy,Vishluck/sympy,yukoba/sympy,mcdaniel67/sympy,maniteja123/sympy,jamesblunt/sympy,abhiii5459/sympy,garvitr/sympy,Gadal/sympy,Sumith1896/sympy,yashsharan/sympy,madan96/sympy,shipci/sympy,VaibhavAgarwalVA/sympy,wyom/sympy,kevalds51/sympy,cswiercz/sympy,maniteja123/sympy,MechCoder/sympy,Davidjohnwilson/sympy,Mitchkoens/sympy,liangjiaxing/sympy,kmacinnis/sympy,sahilshekhawat/sympy,jaimahajan1997/sympy,MridulS/sympy,VaibhavAgarwalVA/sympy,diofant/diofant,jerli/sympy,iamutkarshtiwari/sympy,ga7g08/sympy,jaimahajan1997/sympy,meghana1995/sympy,sahmed95/sympy,pandeyadarsh/sympy,kaushik94/sympy,aktech/sympy,cccfran/sympy,farhaanbukhsh/sympy,abloomston/sympy,garvitr/sympy,jbbskinny/sympy,ChristinaZografou/sympy,sahmed95/sympy,rahuldan/sympy,kevalds51/sympy,jbbskinny/sympy,oliverlee/sympy,grevutiu-gabriel/sympy,saurabhjn76/sympy,vipulroxx/sympy,moble/sympy,pandeyadarsh/sympy,sahmed95/sympy,yashsharan/sympy,toolforger/sympy,garvitr/sympy,jamesblunt/sympy,kaushik94/sympy,madan96/sympy,amitjamadagni/sympy,Gadal/sympy,chaffra/sympy,atsao72/sympy,wyom/sympy,debugger22/sympy,Curious72/sympy,skidzo/sympy,drufat/sympy,atsao72/sympy,ChristinaZografou/sympy,hrashk/sympy,atsao72/sympy,Shaswat27/sympy,Curious72/sympy,MechCoder/sympy,jerli/sympy,lidavidm/sympy,pbrady/sympy,beni55/sympy,souravsingh/sympy,yashsharan/sympy,vipulroxx/sympy,kevalds51/sympy,atreyv/sympy,wyom/sympy,AunShiLord/sympy,hargup/sympy,Shaswat27/sympy,lindsayad/sympy,ahhda/sympy,postvakje/sympy,moble/sympy,jbbskinny/sympy,MridulS/sympy,chaffra/sympy,dqnykamp/sympy,madan96/sympy,wanglongqi/sympy,shipci/sympy,abhiii5459/sympy,farhaanbukhsh/sympy,toolforger/sympy,asm666/sympy,beni55/sympy,bukzor/sympy,souravsingh/sympy,AkademieOlympia/sympy,ahhda/sympy,chaffra/sympy,skirpichev/omg,kmacinnis/sympy,Curious72/sympy,Mitchkoens/sympy,Designist/sympy,jaimahajan1997/sympy,AkademieOlympia/sympy,cccfran/sympy,postvakje/sympy,cswiercz/sympy,shikil/sympy,shikil/sympy,hrashk/sympy,skidzo/sympy,sampadsaha5/sympy,Vishluck/sympy,bukzor/sympy,AkademieOlympia/sympy,maniteja123/sympy,emon10005/sympy,debugger22/sympy,mcdaniel67/sympy,pbrady/sympy,yukoba/sympy,meghana1995/sympy,abloomston/sympy,cccfran/sympy,Davidjohnwilson/sympy,vipulroxx/sympy,lidavidm/sympy,meghana1995/sympy,kaushik94/sympy,moble/sympy,liangjiaxing/sympy,cswiercz/sympy,kmacinnis/sympy,mafiya69/sympy,ga7g08/sympy,sunny94/temp,bukzor/sympy,mafiya69/sympy,abhiii5459/sympy,lindsayad/sympy,hrashk/sympy,skidzo/sympy,sampadsaha5/sympy,emon10005/sympy,kumarkrishna/sympy,hargup/sympy,jamesblunt/sympy,AunShiLord/sympy,shikil/sympy,lidavidm/sympy,emon10005/sympy,AunShiLord/sympy,VaibhavAgarwalVA/sympy,Designist/sympy,atreyv/sympy,lindsayad/sympy,souravsingh/sympy,MechCoder/sympy,Designist/sympy,Gadal/sympy,oliverlee/sympy,Arafatk/sympy,ahhda/sympy,mafiya69/sympy,Davidjohnwilson/sympy,grevutiu-gabriel/sympy,kumarkrishna/sympy,iamutkarshtiwari/sympy,hargup/sympy,atreyv/sympy,kumarkrishna/sympy,asm666/sympy,pbrady/sympy,Arafatk/sympy,saurabhjn76/sympy,Vishluck/sympy,Shaswat27/sympy,Mitchkoens/sympy,aktech/sympy,rahuldan/sympy,sahilshekhawat/sympy,kaichogami/sympy,wanglongqi/sympy,MridulS/sympy