Prevent attempts to initialize the helper code multiple times within a process which can trigger a variety of failures.
Prevent attempts to initialize the helper code multiple times within a process
which can trigger a variety of failures.

Fixes Issue #169.

Thanks to Kumar McMillan for the patch.

ekkleesia3/google-app-engine-django,hitrust/google-app-engine-django,brian-zhao/google-app-engine-django,jackxiang/google-app-engine-django