remove redundant utility code from ExprNodes.py
remove redundant utility code from ExprNodes.py

madjar/cython,mrGeen/cython,c-blake/cython,fperez/cython,acrispin/cython,slonik-az/cython,hhsprings/cython,andreasvc/cython,roxyboy/cython,da-woods/cython,andreasvc/cython,cython/cython,madjar/cython,mrGeen/cython,hhsprings/cython,encukou/cython,marscher/cython,ChristopherHogan/cython,ChristopherHogan/cython,achernet/cython,c-blake/cython,scoder/cython,JelleZijlstra/cython,mcanthony/cython,cython/cython,achernet/cython,mcanthony/cython,c-blake/cython,cython/cython,roxyboy/cython,hickford/cython,scoder/cython,JelleZijlstra/cython,mrGeen/cython,encukou/cython,roxyboy/cython,slonik-az/cython,fperez/cython,fabianrost84/cython,andreasvc/cython,mcanthony/cython,encukou/cython,mrGeen/cython,achernet/cython,dahebolangkuan/cython,ABcDexter/cython,scoder/cython,scoder/cython,achernet/cython,hhsprings/cython,ABcDexter/cython,hickford/cython,fperez/cython,hhsprings/cython,acrispin/cython,madjar/cython,mcanthony/cython,fabianrost84/cython,slonik-az/cython,fabianrost84/cython,marscher/cython,fperez/cython,acrispin/cython,acrispin/cython,hickford/cython,JelleZijlstra/cython,fabianrost84/cython,hickford/cython,marscher/cython,ABcDexter/cython,c-blake/cython,slonik-az/cython,hickford/cython,mcanthony/cython,hhsprings/cython,da-woods/cython,JelleZijlstra/cython,andreasvc/cython,slonik-az/cython,encukou/cython,marscher/cython,dahebolangkuan/cython,c-blake/cython,cython/cython,roxyboy/cython,fabianrost84/cython,JelleZijlstra/cython,ABcDexter/cython,encukou/cython,acrispin/cython,roxyboy/cython,dahebolangkuan/cython,da-woods/cython,dahebolangkuan/cython,dahebolangkuan/cython,andreasvc/cython,ABcDexter/cython,marscher/cython,achernet/cython,fperez/cython,da-woods/cython,mrGeen/cython,madjar/cython,ChristopherHogan/cython,madjar/cython