Python 3.9 is now generally available.

google.appengine.ext.db.put

Store one or more Model instances.

models Model instance or list of Model instances.
config datastore_rpc.Configuration to use for this request, must be specified as a keyword argument.

A Key if models is an instance, a list of Keys in the same order as models if models is a list.

TransactionFailedError if the data could not be committed.