[firedrake] calling firedrake in idle

Dear all, I activated firedrake in the mac terminal and then opened idle from the terminal but I get the following error while trying to import firedrake in idle: Traceback (most recent call last): File "<pyshell#1>", line 1, in <module> from firedrake import * ImportError: No module named firedrake How can I get around this problem? Thanks in advance. Angwenyi