yi@zeus:~/Software/distributed_sage/ > echo $PYTHONPATH
/Users/yi/Software/distributed_sage
yi@zeus:~/Software/distributed_sage/ > python dsage/tests/test_job_database.py 
Traceback (most recent call last):
  File "dsage/tests/test_job_database.py", line 23, in ?
    from dsage.database.job_database import JobDatabaseZODB
ImportError: No module named dsage.database.job_database