simple graphics lib

[Bignose3]

I am a student learning python on my own, coming from a C++ backgroud.
 I am working on a simple project, a simulation of fish, as a way to
gain experience using python.  I am looking for a simple graphics lib
that will allow me to display objects- like circles or squares to
represent the objects I am coding.  Is anyone aware of a lib that will
allow me to do this.  When learning C++ I used the CMU Graphics Lib
which worked great.  Let me know if anyone has any ideas.

Thank You
Joe