def bulk_create(self, objs, batch_size=None):
self._insert(objs, batch_size=batch_size, return_id=False, force_insert=True)<EOL>self.refresh()<EOL>
Inserts each of the instances into the database. This does *not* call
save() on each of the instances, does not send any pre/post save
signals, and does not set the primary key attribute if it is an
autoincrement field.