code: def format_configurablefield_nodes(field_name, field, field_id, state, lineno):
      
      # Custom default target definition list that links to Task topics
      default_item = nodes.definition_list_item()
      default_item.append(nodes.term(text="Default"))
      default_item_content = nodes.definition()
      para = nodes.paragraph()
      name = '.'.join((field.target.__module__, field.target.__name__))
      para += pending_task_xref(rawsource=name)
      default_item_content += para
      default_item += default_item_content
  
      # Definition list for key-value metadata
      dl = nodes.definition_list()
      dl += default_item
      dl += create_field_type_item_node(field, state)
  
      # Doc for this ConfigurableField, parsed as rst
      desc_node = create_description_node(field, state)
  
      # Title for configuration field
      title = create_title_node(field_name, field, field_id, state, lineno)
  
      return [title, dl, desc_node]
docs: Create a section node that documents a ConfigurableField config field.
  
      Parameters
      ----------
      field_name : `str`
          Name of the configuration field (the attribute name of on the config
          class).
      field : ``lsst.pex.config.ConfigurableField``
          A configuration field.
      field_id : `str`
          Unique identifier for this field. This is used as the id and name of
          the section node. with a -section suffix
      state : ``docutils.statemachine.State``
          Usually the directive's ``state`` attribute.
      lineno (`int`)
          Usually the directive's ``lineno`` attribute.
  
      Returns
      -------
      ``docutils.nodes.section``
          Section containing documentation nodes for the ConfigurableField.