def execute(self, write_concern=None):
        """Execute all provided operations.

        :Parameters:
          - write_concern (optional): the write concern for this bulk
            execution.
        """
        if write_concern is not None:
            write_concern = WriteConcern(**write_concern)
        return self.__bulk.execute(write_concern, session=None)
Execute all provided operations.

        :Parameters:
          - write_concern (optional): the write concern for this bulk
            execution.
        
stackoverflow/venv/lib/python3.6/site-packages/pymongo/bulk.py