The startup of dev_appserver.py in appengine in Ubuntu reports that the PILmodule's warning solution is missing.

Use the pythondev_appserver.py site name in Ubuntu to start site debugging. Sometimes you can see two errors. One error is that the datastore-related warning cannot be found, this is because the site was started for the first time, followed by this error: "CouldnotinitializeimagesAPI" youarelikelymissingthePython "PIL" module. imp

Use the python dev_appserver.py site name in Ubuntu to start site debugging. Sometimes you can see two errors. One error is that the datastore-related warning cannot be found, this is because the site was started for the first time, followed by this error:

"Cocould not initialize images API" you are likely missing the Python "PIL" module. ImportError: No module named PIL

The PIL module can also be replaced by other modules, but if you want to use Python Image Library, run

Sudo apt-get install python-imaging.