FIX: add _supports_fileno() for testing fileno()
FIX: add _supports_fileno() for testing fileno()

The new _supports_fileno() function works in all versions of Python.
The problem was that in Python 2.x, the fileno() method of StringIO() is
missing, while in Python 3.x, it is present, but raises an exception.

mortada/numpy,KaelChen/numpy,jschueller/numpy,rhythmsosad/numpy,andsor/numpy,ContinuumIO/numpy,Eric89GXL/numpy,hainm/numpy,utke1/numpy,mattip/numpy,maniteja123/numpy,ekalosak/numpy,andsor/numpy,jankoslavic/numpy,jorisvandenbossche/numpy,ssanderson/numpy,hainm/numpy,solarjoe/numpy,groutr/numpy,rhythmsosad/numpy,ogrisel/numpy,seberg/numpy,pbrod/numpy,rgommers/numpy,sinhrks/numpy,anntzer/numpy,simongibbons/numpy,mortada/numpy,ChanderG/numpy,rmcgibbo/numpy,drasmuss/numpy,shoyer/numpy,seberg/numpy,naritta/numpy,larsmans/numpy,ddasilva/numpy,joferkington/numpy,joferkington/numpy,sigma-random/numpy,MSeifert04/numpy,ogrisel/numpy,ahaldane/numpy,behzadnouri/numpy,rajathkumarmp/numpy,GrimDerp/numpy,hainm/numpy,Yusa95/numpy,mhvk/numpy,tynn/numpy,cowlicks/numpy,mwiebe/numpy,skymanaditya1/numpy,WarrenWeckesser/numpy,nguyentu1602/numpy,ChristopherHogan/numpy,rudimeier/numpy,mindw/numpy,larsmans/numpy,leifdenby/numpy,anntzer/numpy,endolith/numpy,MichaelAquilina/numpy,yiakwy/numpy,embray/numpy,githubmlai/numpy,Anwesh43/numpy,ChanderG/numpy,BMJHayward/numpy,WarrenWeckesser/numpy,sonnyhu/numpy,Srisai85/numpy,mattip/numpy,rmcgibbo/numpy,GrimDerp/numpy,argriffing/numpy,jakirkham/numpy,rajathkumarmp/numpy,Linkid/numpy,dimasad/numpy,MaPePeR/numpy,jschueller/numpy,ChristopherHogan/numpy,dch312/numpy,Eric89GXL/numpy,cowlicks/numpy,GrimDerp/numpy,mhvk/numpy,kirillzhuravlev/numpy,sinhrks/numpy,argriffing/numpy,pyparallel/numpy,WarrenWeckesser/numpy,grlee77/numpy,kiwifb/numpy,pizzathief/numpy,skwbc/numpy,pbrod/numpy,moreati/numpy,Anwesh43/numpy,charris/numpy,MSeifert04/numpy,tdsmith/numpy,ViralLeadership/numpy,chatcannon/numpy,CMartelLML/numpy,MSeifert04/numpy,ogrisel/numpy,Eric89GXL/numpy,yiakwy/numpy,naritta/numpy,kiwifb/numpy,embray/numpy,kirillzhuravlev/numpy,ViralLeadership/numpy,MichaelAquilina/numpy,NextThought/pypy-numpy,jonathanunderwood/numpy,ekalosak/numpy,rmcgibbo/numpy,simongibbons/numpy,skymanaditya1/numpy,jakirkham/numpy,mathdd/numpy,WarrenWeckesser/numpy,immerrr/numpy,shoyer/numpy,ajdawson/numpy,bmorris3/numpy,cjermain/numpy,tdsmith/numpy,dimasad/numpy,rgommers/numpy,charris/numpy,mattip/numpy,WarrenWeckesser/numpy,mattip/numpy,skymanaditya1/numpy,pizzathief/numpy,nguyentu1602/numpy,embray/numpy,ahaldane/numpy,groutr/numpy,BMJHayward/numpy,pizzathief/numpy,ssanderson/numpy,felipebetancur/numpy,sigma-random/numpy,stuarteberg/numpy,cowlicks/numpy,mindw/numpy,jakirkham/numpy,abalkin/numpy,Eric89GXL/numpy,felipebetancur/numpy,sinhrks/numpy,mingwpy/numpy,drasmuss/numpy,mindw/numpy,tacaswell/numpy,dato-code/numpy,SiccarPoint/numpy,jankoslavic/numpy,GaZ3ll3/numpy,ddasilva/numpy,kirillzhuravlev/numpy,ekalosak/numpy,grlee77/numpy,KaelChen/numpy,joferkington/numpy,musically-ut/numpy,trankmichael/numpy,madphysicist/numpy,gmcastil/numpy,tacaswell/numpy,nbeaver/numpy,dwillmer/numpy,rudimeier/numpy,solarjoe/numpy,githubmlai/numpy,pbrod/numpy,yiakwy/numpy,rherault-insa/numpy,WillieMaddox/numpy,nguyentu1602/numpy,rajathkumarmp/numpy,GaZ3ll3/numpy,bmorris3/numpy,jorisvandenbossche/numpy,trankmichael/numpy,madphysicist/numpy,b-carter/numpy,larsmans/numpy,pbrod/numpy,pdebuyl/numpy,andsor/numpy,BabeNovelty/numpy,endolith/numpy,immerrr/numpy,pyparallel/numpy,skwbc/numpy,empeeu/numpy,Linkid/numpy,ESSS/numpy,leifdenby/numpy,grlee77/numpy,has2k1/numpy,ChristopherHogan/numpy,SiccarPoint/numpy,dato-code/numpy,ahaldane/numpy,bmorris3/numpy,ajdawson/numpy,GaZ3ll3/numpy,pdebuyl/numpy,ahaldane/numpy,maniteja123/numpy,gmcastil/numpy,jankoslavic/numpy,anntzer/numpy,GaZ3ll3/numpy,cjermain/numpy,charris/numpy,njase/numpy,MichaelAquilina/numpy,MSeifert04/numpy,MaPePeR/numpy,rajathkumarmp/numpy,KaelChen/numpy,brandon-rhodes/numpy,ViralLeadership/numpy,pizzathief/numpy,has2k1/numpy,shoyer/numpy,ogrisel/numpy,rudimeier/numpy,Yusa95/numpy,stuarteberg/numpy,madphysicist/numpy,trankmichael/numpy,ddasilva/numpy,endolith/numpy,numpy/numpy,empeeu/numpy,AustereCuriosity/numpy,WillieMaddox/numpy,ContinuumIO/numpy,immerrr/numpy,jakirkham/numpy,MaPePeR/numpy,CMartelLML/numpy,has2k1/numpy,dch312/numpy,githubmlai/numpy,leifdenby/numpy,dch312/numpy,rherault-insa/numpy,SiccarPoint/numpy,simongibbons/numpy,sonnyhu/numpy,AustereCuriosity/numpy,chiffa/numpy,mathdd/numpy,BabeNovelty/numpy,behzadnouri/numpy,cowlicks/numpy,mortada/numpy,sigma-random/numpy,sinhrks/numpy,drasmuss/numpy,seberg/numpy,chiffa/numpy,Srisai85/numpy,jakirkham/numpy,tdsmith/numpy,jorisvandenbossche/numpy,mwiebe/numpy,anntzer/numpy,NextThought/pypy-numpy,BMJHayward/numpy,NextThought/pypy-numpy,jschueller/numpy,ChristopherHogan/numpy,kirillzhuravlev/numpy,MaPePeR/numpy,groutr/numpy,CMartelLML/numpy,bringingheavendown/numpy,jschueller/numpy,dch312/numpy,trankmichael/numpy,chiffa/numpy,sigma-random/numpy,rgommers/numpy,bmorris3/numpy,dimasad/numpy,nbeaver/numpy,pdebuyl/numpy,bringingheavendown/numpy,tdsmith/numpy,brandon-rhodes/numpy,WillieMaddox/numpy,larsmans/numpy,jorisvandenbossche/numpy,dwillmer/numpy,ESSS/numpy,njase/numpy,sonnyhu/numpy,ContinuumIO/numpy,SunghanKim/numpy,SiccarPoint/numpy,naritta/numpy,gfyoung/numpy,madphysicist/numpy,jonathanunderwood/numpy,NextThought/pypy-numpy,pyparallel/numpy,brandon-rhodes/numpy,rgommers/numpy,embray/numpy,mortada/numpy,madphysicist/numpy,SunghanKim/numpy,bringingheavendown/numpy,empeeu/numpy,ESSS/numpy,b-carter/numpy,mindw/numpy,embray/numpy,BabeNovelty/numpy,andsor/numpy,cjermain/numpy,MSeifert04/numpy,ChanderG/numpy,Dapid/numpy,dato-code/numpy,moreati/numpy,brandon-rhodes/numpy,skwbc/numpy,mathdd/numpy,argriffing/numpy,behzadnouri/numpy,bertrand-l/numpy,ogrisel/numpy,bertrand-l/numpy,ssanderson/numpy,rhythmsosad/numpy,empeeu/numpy,BabeNovelty/numpy,numpy/numpy,jankoslavic/numpy,tacaswell/numpy,sonnyhu/numpy,ajdawson/numpy,chatcannon/numpy,pbrod/numpy,chatcannon/numpy,ahaldane/numpy,musically-ut/numpy,Dapid/numpy,yiakwy/numpy,gfyoung/numpy,felipebetancur/numpy,stuarteberg/numpy,mingwpy/numpy,gfyoung/numpy,Yusa95/numpy,jonathanunderwood/numpy,KaelChen/numpy,Linkid/numpy,pdebuyl/numpy,utke1/numpy,mathdd/numpy,mhvk/numpy,simongibbons/numpy,has2k1/numpy,mingwpy/numpy,b-carter/numpy,felipebetancur/numpy,ajdawson/numpy,njase/numpy,charris/numpy,rherault-insa/numpy,gmcastil/numpy,ChanderG/numpy,numpy/numpy,mwiebe/numpy,pizzathief/numpy,grlee77/numpy,endolith/numpy,simongibbons/numpy,joferkington/numpy,Yusa95/numpy,SunghanKim/numpy,tynn/numpy,seberg/numpy,BMJHayward/numpy,SunghanKim/numpy,GrimDerp/numpy,rhythmsosad/numpy,solarjoe/numpy,jorisvandenbossche/numpy,AustereCuriosity/numpy,Srisai85/numpy,shoyer/numpy,Linkid/numpy,immerrr/numpy,abalkin/numpy,musically-ut/numpy,grlee77/numpy,MichaelAquilina/numpy,nguyentu1602/numpy,rmcgibbo/numpy,dwillmer/numpy,dimasad/numpy,naritta/numpy,skymanaditya1/numpy,Anwesh43/numpy,hainm/numpy,mhvk/numpy,nbeaver/numpy,tynn/numpy,mhvk/numpy,numpy/numpy,CMartelLML/numpy,rudimeier/numpy,Dapid/numpy,dwillmer/numpy,cjermain/numpy,abalkin/numpy,Anwesh43/numpy,maniteja123/numpy,bertrand-l/numpy,githubmlai/numpy,stuarteberg/numpy,moreati/numpy,kiwifb/numpy,utke1/numpy,ekalosak/numpy,shoyer/numpy,mingwpy/numpy,dato-code/numpy,musically-ut/numpy,Srisai85/numpy