import obspy hangs terminal

I am running a Mac, version 10.10.5 (Yosemite)

I type the following in my terminal window:

python (to start python 2.7.10)

import obspy

THEN MY TERMINAL WINDOW JUST HANGS, NO RESPONSE TO KEYBOARD

please help

Thanks,

Mark

Mark Goldman
U.S. Geological Survey
345 Middlefield Rd, MS 977
Menlo Park, CA 94025
goldman@usgs.gov
650-329-5496