code: def calc_mb_ports(self):
          
          model = self.device_info['model']
          chassis = self.device_info['chassis']
          num_ports = MODEL_MATRIX[model][chassis]['ports']
          ports = []
  
          if num_ports > 0:
              port_type = MODEL_MATRIX[model][chassis]['type']
  
              # Create the ports dict
              for i in range(num_ports):
                  port_temp = {'name': PORT_TYPES[port_type] + '0/' + str(i),
                               'id': self.port_id,
                               'port_number': i,
                               'slot_number': 0}
                  ports.append(port_temp)
                  self.port_id += 1
          self.node['ports'].extend(ports)
docs: Add the default ports to add to a router