How to know/change current directory in Python shell?

Question

I am using Python 3.2 on Windows 7. When I open the Python shell, how can I know what the current directory is and how can I change it to another directory where my modules

Answer 1

>>> import os
>>> os.system('cd c:\mydir')

In fact, os.system() can execute any command that windows command prompt can execute, not just change dir.