Normally, when a python module is imported, python automatically generate a .pyc file containing the compiled byte code. The next time the same program is run, the compilation step can thus be skipped.

However, in order to manually pre-compile the python modules even before running them, here are two ways of doing it:

1. Use a python script

   • To compile a single file / module, use the py_compile module.

     import py_compile
     if __name__ == "__main__":
         py_compile.compile('abc.py')
     

   • To compile all files in a directory, use the compileall module.

     import compileall
     if __name__ == "__main__":
         compileall.compile_dir('Lib/')
     

2. Execute on a shell / command line.

   • The compileall module can also be invoked as a script. On the command line, type:

     python -m compileall Lib\