How to launch cmd window, and excute command within the cmd window with Python script

[vivawind]

I want to write a Python script to do following:
1. launch cmd window
2. execute dos command within cmd window.

I tried following:

command = r'start "test" cmd'
os.system(command)

=> it is able to launch a cmd window with "test" title.

What is the syntax for not only launch the cmd window, but also able to execute a command, like run a python script.

I tried to do
command = r 'start "test" cmd ("dir")'
- expect it launch the cmd window, and excute "dir" command, doesn't work.

[dwblas]

Try Pexpect, a Python module written to run programs and watch their output from Python.

[vivawind]

Before I spend time studying the Pexpect as you mentioned, wondering if this works well under Window's environment. If not, what will be the solution?