Move TODO about isDeletable Sponsor logic method to sponsor.py module and extend a little bit doc string.
Patch by: Pawel Solyga
Review by: to-be-reviewed
indexes:
# AUTOGENERATED
# This index.yaml is automatically updated whenever the dev_appserver
# detects that a new type of query is run. If you want to manage the
# index.yaml file manually, remove the above marker line (the line
# saying "# AUTOGENERATED"). If you want to manage some indexes
# manually, move them above the marker line. The index.yaml file is
# automatically uploaded to the admin console when you next deploy
# your application using appcfg.py.