code: public static Integer imports(Configurer configurer)
      {
          Check.notNull(configurer);
  
          if (configurer.hasNode(NODE_GROUP))
          {
              final String group = configurer.getText(NODE_GROUP);
              try
              {
                  return Integer.valueOf(group);
              }
              catch (final NumberFormatException exception)
              {
                  throw new LionEngineException(exception, ERROR_INVALID_GROUP + group);
              }
          }
  
          return DEFAULT_GROUP;
      }
docs: Create the collidable data from node.
  
  @param configurer The configurer reference (must not be <code>null</code>).
  @return The associated group, {@link #DEFAULT_GROUP} if not defined.
  @throws LionEngineException If unable to read node.