code: def format_body(self, description, sys_info=None, traceback=None):
          
          name = 'Description'
          delim = '-' * 40
          body = BODY_ITEM_TEMPLATE % {
              'name': name, 'value': description, 'delim': delim
          }
          if traceback:
              name = 'Traceback'
              traceback = '\n'.join(traceback.splitlines()[-NB_LINES_MAX:])
              body += BODY_ITEM_TEMPLATE % {
                  'name': name, 'value': traceback, 'delim': delim
              }
          if sys_info:
              name = 'System information'
              body += BODY_ITEM_TEMPLATE % {
                  'name': name, 'value': sys_info, 'delim': delim
              }
          return body
docs: Formats the body in plain text. (add a series of '-' under each section
              title).
  
          :param description: Description of the issue, written by the user.
          :param sys_info: Optional system information string
          :param log: Optional application log
          :param traceback: Optional traceback.