code: def add_source_files(
              self,
              source_filenames_or_globs: Union[str, List[str]],
              method: AutodocMethod = None,
              recursive: bool = None,
              source_rst_title_style_python: bool = None,
              pygments_language_override: Dict[str, str] = None) -> None:
          
          if not source_filenames_or_globs:
              return
  
          if method is None:
              # Use the default
              method = self.method
          if recursive is None:
              recursive = self.recursive
          if source_rst_title_style_python is None:
              source_rst_title_style_python = self.source_rst_title_style_python
          if pygments_language_override is None:
              pygments_language_override = self.pygments_language_override
  
          # Get a sorted list of filenames
          final_filenames = self.get_sorted_source_files(
              source_filenames_or_globs,
              recursive=recursive
          )
  
          # Process that sorted list
          for source_filename in final_filenames:
              self.files_to_index.append(FileToAutodocument(
                  source_filename=source_filename,
                  project_root_dir=self.project_root_dir,
                  python_package_root_dir=self.python_package_root_dir,
                  target_rst_filename=self.specific_file_rst_filename(
                      source_filename
                  ),
                  method=method,
                  source_rst_title_style_python=source_rst_title_style_python,
                  pygments_language_override=pygments_language_override,
              ))
docs: Adds source files to the index.
  
          Args:
              source_filenames_or_globs: string containing a filename or a
                  glob, describing the file(s) to be added, or a list of such
                  strings
              method: optional method to override ``self.method``
              recursive: use :func:`glob.glob` in recursive mode? (If ``None``,
                  the default, uses the version from the constructor.)
              source_rst_title_style_python: optional to override
                  ``self.source_rst_title_style_python``
              pygments_language_override: optional to override
                  ``self.pygments_language_override``