open http://www.python.org
click "Lauch Interactive Shell"

In [1]: import subprocess

In [2]: subprocess.call("emacs")

Welcome to GNU Emacs, one component of the GNU/Linux
operating system.
....

-UUU:%%--F1 *GNU Emacs* Top L1 (Fundamental)--------
For information about GNU Emacs, type C-h C-a.