code: def add_section(self, section):
          
          if section in self.sections():
              raise DuplicateSectionError(section)
          if isinstance(section, str):
              # create a new section
              section = Section(section, container=self)
          elif not isinstance(section, Section):
              raise ValueError("Parameter must be a string or Section type!")
          self._structure.append(section)
docs: Create a new section in the configuration.
  
          Raise DuplicateSectionError if a section by the specified name
          already exists. Raise ValueError if name is DEFAULT.
  
          Args:
              section (str or :class:`Section`): name or Section type