def save(self, must_create=False):
if self.session_key is None:<EOL><INDENT>return self.create()<EOL><DEDENT>data = self._get_session(no_load=must_create)<EOL>obj = self.create_model_instance(data)<EOL>obj.save()<EOL>
Saves the current session data to the database. If 'must_create' is
True, a database error will be raised if the saving operation doesn't
create a *new* entry (as opposed to possibly updating an existing
entry).

:param must_create: