code: def _add_notice_to_docstring(doc, no_doc_str, notice):
      
      if not doc:
          lines = [no_doc_str]
  
      else:
          lines = _normalize_docstring(doc).splitlines()
  
      notice = [''] + notice
  
      if len(lines) > 1:
          # Make sure that we keep our distance from the main body
          if lines[1].strip():
              notice.append('')
  
          lines[1:1] = notice
      else:
          lines += notice
  
      return '\n'.join(lines)
docs: Adds a deprecation notice to a docstring.