Returns a list of tuples of (block id, BlockStatus) pairs.

def get_block_statuses(self, block_ids):
        """Returns a list of tuples of (block id, BlockStatus) pairs.
        """
        try:
            return [
                (block_id.hex(),
                 self._chain_controller.block_validation_result(
                     block_id.hex()))
                for block_id in block_ids
            ]
        except KeyError as key_error:
            raise UnknownBlock(key_error.args[0])