combinatorics/test_graycode: Don't test random function
combinatorics/test_graycode: Don't test random function

This test produced an error under Python 3, as the random function
changed. It was also setting the seed, which was interfering with the
test runner setting the seed. Change test to check if output is
semantically correct, but not what it actually is.

shikil/sympy,sunny94/temp,debugger22/sympy,abhiii5459/sympy,aktech/sympy,Gadal/sympy,shipci/sympy,oliverlee/sympy,jbbskinny/sympy,sahmed95/sympy,hargup/sympy,abloomston/sympy,debugger22/sympy,cswiercz/sympy,Vishluck/sympy,AkademieOlympia/sympy,jaimahajan1997/sympy,grevutiu-gabriel/sympy,shipci/sympy,Sumith1896/sympy,Davidjohnwilson/sympy,beni55/sympy,Designist/sympy,lidavidm/sympy,MechCoder/sympy,vipulroxx/sympy,wyom/sympy,saurabhjn76/sympy,MechCoder/sympy,MridulS/sympy,madan96/sympy,kumarkrishna/sympy,souravsingh/sympy,Mitchkoens/sympy,VaibhavAgarwalVA/sympy,wyom/sympy,grevutiu-gabriel/sympy,pandeyadarsh/sympy,lidavidm/sympy,atreyv/sympy,flacjacket/sympy,sahmed95/sympy,VaibhavAgarwalVA/sympy,sunny94/temp,abloomston/sympy,kaushik94/sympy,toolforger/sympy,kumarkrishna/sympy,Vishluck/sympy,cccfran/sympy,ga7g08/sympy,garvitr/sympy,abloomston/sympy,hrashk/sympy,Curious72/sympy,saurabhjn76/sympy,wanglongqi/sympy,vipulroxx/sympy,sahmed95/sympy,shikil/sympy,rahuldan/sympy,pbrady/sympy,kevalds51/sympy,moble/sympy,mafiya69/sympy,MridulS/sympy,pbrady/sympy,chaffra/sympy,sahilshekhawat/sympy,aktech/sympy,ahhda/sympy,skirpichev/omg,maniteja123/sympy,rahuldan/sympy,pandeyadarsh/sympy,pandeyadarsh/sympy,maniteja123/sympy,Shaswat27/sympy,chaffra/sympy,ChristinaZografou/sympy,ChristinaZografou/sympy,yashsharan/sympy,kmacinnis/sympy,farhaanbukhsh/sympy,dqnykamp/sympy,garvitr/sympy,grevutiu-gabriel/sympy,aktech/sympy,sahilshekhawat/sympy,skidzo/sympy,souravsingh/sympy,kaushik94/sympy,kaichogami/sympy,chaffra/sympy,emon10005/sympy,amitjamadagni/sympy,ga7g08/sympy,shipci/sympy,atreyv/sympy,Gadal/sympy,asm666/sympy,Curious72/sympy,oliverlee/sympy,yukoba/sympy,postvakje/sympy,atreyv/sympy,kevalds51/sympy,kumarkrishna/sympy,jerli/sympy,hrashk/sympy,VaibhavAgarwalVA/sympy,jaimahajan1997/sympy,sunny94/temp,bukzor/sympy,cccfran/sympy,hargup/sympy,jbbskinny/sympy,Titan-C/sympy,atsao72/sympy,yashsharan/sympy,MridulS/sympy,atsao72/sympy,mcdaniel67/sympy,kaichogami/sympy,Sumith1896/sympy,saurabhjn76/sympy,AunShiLord/sympy,postvakje/sympy,Arafatk/sympy,atsao72/sympy,jerli/sympy,asm666/sympy,Mitchkoens/sympy,mcdaniel67/sympy,lindsayad/sympy,srjoglekar246/sympy,jaimahajan1997/sympy,kaushik94/sympy,farhaanbukhsh/sympy,meghana1995/sympy,debugger22/sympy,lindsayad/sympy,toolforger/sympy,AkademieOlympia/sympy,wanglongqi/sympy,mafiya69/sympy,beni55/sympy,toolforger/sympy,Curious72/sympy,drufat/sympy,beni55/sympy,dqnykamp/sympy,cswiercz/sympy,kaichogami/sympy,moble/sympy,sampadsaha5/sympy,liangjiaxing/sympy,shikil/sympy,garvitr/sympy,madan96/sympy,wanglongqi/sympy,jamesblunt/sympy,souravsingh/sympy,lindsayad/sympy,moble/sympy,jerli/sympy,Gadal/sympy,AunShiLord/sympy,madan96/sympy,meghana1995/sympy,skidzo/sympy,jbbskinny/sympy,drufat/sympy,asm666/sympy,wyom/sympy,maniteja123/sympy,cswiercz/sympy,meghana1995/sympy,kmacinnis/sympy,AkademieOlympia/sympy,hargup/sympy,emon10005/sympy,skidzo/sympy,MechCoder/sympy,pbrady/sympy,Arafatk/sympy,Davidjohnwilson/sympy,diofant/diofant,farhaanbukhsh/sympy,Titan-C/sympy,lidavidm/sympy,drufat/sympy,abhiii5459/sympy,rahuldan/sympy,sahilshekhawat/sympy,Davidjohnwilson/sympy,iamutkarshtiwari/sympy,liangjiaxing/sympy,bukzor/sympy,ahhda/sympy,emon10005/sympy,Designist/sympy,iamutkarshtiwari/sympy,kevalds51/sympy,yukoba/sympy,Mitchkoens/sympy,jamesblunt/sympy,amitjamadagni/sympy,iamutkarshtiwari/sympy,sampadsaha5/sympy,Sumith1896/sympy,Shaswat27/sympy,AunShiLord/sympy,vipulroxx/sympy,ga7g08/sympy,cccfran/sympy,jamesblunt/sympy,ChristinaZografou/sympy,dqnykamp/sympy,Shaswat27/sympy,oliverlee/sympy,Designist/sympy,hrashk/sympy,Arafatk/sympy,yashsharan/sympy,sampadsaha5/sympy,mcdaniel67/sympy,kmacinnis/sympy,mafiya69/sympy,postvakje/sympy,abhiii5459/sympy,bukzor/sympy,yukoba/sympy,liangjiaxing/sympy,Titan-C/sympy,ahhda/sympy,Vishluck/sympy