Andrey Smirnov

Do you have the Python header files installed? Try running the command (for CentOS): ``` yum install python-devel ``` Or for Debian/Ubuntu: ``` apt-get install python-dev ```

@mahdilou99 It looks like a network problem. DNS is not configured correctly.

You have installed python-devel version 2.7 but you are using pip version 3.6. Try run the following command and install the correct version of python-devel. ``` yum search python-devel ```