Python 3.9 is now generally available.

google.appengine.api.datastore.CreateConfig

Create a Configuration object for use in configuring datastore calls.

This configuration can be passed to most datastore calls using the 'config=...' argument.

deadline Optional deadline; default None (which means the system default deadline will be used, typically 5 seconds).
on_completion Optional callback function; default None. If specified, it will be called with a UserRPC object as argument when an RPC completes.
read_policy Optional read policy; set to EVENTUAL_CONSISTENCY to enable eventually consistent reads (i.e. reads that may be satisfied from an older version of the datastore in some cases). The default read policy may have to wait until in-flight transactions are committed.
**kwds Other keyword arguments as long as they are supported by datastore_rpc.Configuration().

A datastore_rpc.Configuration instance.