fix mechanics doc examples to use normalize()
fix mechanics doc examples to use normalize()

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