code: def rpc_get_consensus_at( self, block_id, **con_info ):
          
          if not check_block(block_id):
              return {'error': 'Invalid block height', 'http_status': 400}
  
          db = get_db_state(self.working_dir)
          consensus = db.get_consensus_at( block_id )
          db.close()
          return self.success_response( {'consensus': consensus} )
docs: Return the consensus hash at a block number.
          Return {'status': True, 'consensus': ...} on success
          Return {'error': ...} on error