parsers/sympy_tokenize: remove del statement
parsers/sympy_tokenize: remove del statement

Commit e282b5de copied Python's tokenize.py with some modifications to
sympy_tokenize, including a "del x" statement. This statement fails in
Python 3 with a NameError; in Python 3, variables used in list
comprehensions are no longer in the namespace so there is nothing to
delete. This line was eliminated upstream with changeset
41464:060c79f6d919: "Hide list comp variables and support set
comprehensions", so delete it here as well.

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