Centos 6 is 7 years old, if you are still using that it is unfortunately your problem. It's not hard to write "python3" on a modern dist.
Ubuntu has 3.5 and 3.6 is easily installable though not yet default 3.x.
Ubuntu has 3.5 and 3.6 is easily installable though not yet default 3.x.
Py 2.6 is already EOL for almost five years.
Is he making that assumption, or are you?