code: def add_section(self, name):
          
  
          assert isinstance(name, str)
  
          # Skip existing sections
          for section in self.sections:
              if section.name == name:
                  return section
  
          item = defaults["common"].copy()
          item["name"] = name
  
          item["itemType"] = "section"
  
          item = self.add_item(item)
          self.sections.append(item)
  
          return item
docs: Append `section` to model
  
          Arguments:
              name (str): Name of section