'Transactionally retrieves an existing entity or creates a new one.
Positional Args:
name: Key name to retrieve or create.
Keyword Args:
namespace: Optional namespace.
app: Optional app ID.
parent: Parent entity key, if any.
context_options: ContextOptions object (not keyword args!) or None.
**kwds: Keyword arguments to pass to the constructor of the model class
if an instance for the specified key name does not already exist. If
an instance with the supplied key_name and parent already exists,
these arguments will be discarded.
Returns:
Existing instance of Model class with the specified key name and parent
or a new one that has just been created.'

@classmethod
def _get_or_insert(*args, **kwds):

    (cls, args) = (args[0], args[1:])
    return cls._get_or_insert_async(*args, **kwds).get_result()
