/usr/bin/python: No module named s4cmd

On CentOS 6.7 with python 2.6 system default and python 3.4 side by side via IUS Community repo

```
locate /usr/bin/pip
/usr/bin/pip
/usr/bin/pip3
/usr/bin/pip3.4

pip --version
pip 7.1.2 from /usr/lib/python3.4/site-packages (python 3.4)

python --version
Python 2.6.6
```

I installed s4cmd via

```
pip install s4cmd
```

but get

```
s4cmd
/usr/bin/python: No module named s4cmd
```

best way to correct this ?

Start by comparing the Python interpreter used by `pip install s4cmd` with the `/usr/bin/python` interpreter invoked by the `s4cmd` command. Reproduce the reported CentOS 6.7 setup and confirm that the command runs successfully with the installed module.

Written by the indexing model from the issue text.