just use python 2.7 for now
just use python 2.7 for now

Signed-off-by: Alfredo Deza <3ae498813ac9b6992b3bb72690656738fc9b4e19@inktank.com>

dmick/teuthology,robbat2/teuthology,SUSE/teuthology,tchaikov/teuthology,t-miyamae/teuthology,dmick/teuthology,SUSE/teuthology,ceph/teuthology,ktdreyer/teuthology,yghannam/teuthology,dreamhost/teuthology,t-miyamae/teuthology,caibo2014/teuthology,michaelsevilla/teuthology,caibo2014/teuthology,zhouyuan/teuthology,dreamhost/teuthology,zhouyuan/teuthology,ivotron/teuthology,robbat2/teuthology,dmick/teuthology,tchaikov/teuthology,ceph/teuthology,ivotron/teuthology,SUSE/teuthology,ktdreyer/teuthology,michaelsevilla/teuthology,yghannam/teuthology