Login causes the provided Request to act as though issued by the given user.

Logout causes the provided Request to act as though issued by a logged-out user.

NewContext starts an instance of the development API server, and returns a context that will route all API calls to that server, as well as a closure that must be called when the Context is no longer required.

NewInstance launches a running instance of api_server.py which can be used for multiple test Contexts that delegate all App Engine API calls to that instance.

PrepareDevAppserver is a hook which, if set, will be called before the dev_appserver.py is started, each time it is started.

Options is used to specify options when creating an Instance.

Instance represents a running instance of the development API Server.