You can create an alias to 2.7 as 3 :
sudo ln -s /usr/bin/python2.7 /usr/bin/python3
To check your default python version use the command:
python --version
You may check your python executable, versus the location of lib site-packages.
Your site-packages should be in the directory:
~/usr/lib/python2.7/site-packages
And your executable could be in the directory:
~/usr/bin
To check where it is finding the executables run the command:
which python
which python2.7
which pythohn3