All the FreeSwitch documentations are given assuming you have installed Debian. So for CentOs or any RHEL distribution users are having a problem.
When I tried to follow the  mod_python documentation given by FreeSwitch, I am getting errors.
Now, How can I install mod_python or any other modules?
In CentOs for installing any software, search the yum repo.
Like here,
I ran
yum search freeswitch
I got all the FreeSwitch modules. Now find your required modules and install.
Like here for mod_python module, I typed
yum install freeswitch-python.x86_64

Now, type  cd /etc/freeswitch/autoload_configs/ and edit modules.conf.xml
Add <load module="mod_python"/> and save the file and exit.
Now, use fs_cli command and type reloadxml.
After this restart your linux system and again type fs_cli and type module_exists mod_python.
This should show true. If so, that means mod_python installation is successful.
FreeSwitch mod_python(or any other modules) installation on CentOs 7