          return str(self._regex)
  
  
  _PATH_PARAMETER_COMPONENT_RE = _lazy_re_compile(
      r'<(?:(?P<converter>[^>:]+):)?(?P<parameter>\w+)>'
  )
  
  
  def _route_to_regex(route, is_endpoint=False):
      """
 
</s> remove         expected_msg = "Your URL pattern '(?P<named-group>\\d+)' has a route"
 </s> add         expected_msg = "Your URL pattern '(?P<named_group>\\d+)' has a route" </s> remove     def test_non_identifier_parameter_name_causes_exception(self):
 </s> add     def test_integer_parameter_name_causes_exception(self): </s> remove     path(r'(?P<named-group>\d+)', lambda x: x),
 </s> add     path(r'(?P<named_group>\d+)', lambda x: x), </s> remove         'sitemaps/kml/<label>/<<model>/<field_name>.kmz',
 </s> add         'sitemaps/kml/<label>/<model>/<field_name>.kmz',
    r'<(?:(?P<converter>[^>:]+):)?(?P<parameter>[^>]+)>'
          return str(self._regex)
  
  
  _PATH_PARAMETER_COMPONENT_RE = _lazy_re_compile(
    r'<(?:(?P<converter>[^>:]+):)?(?P<parameter>[^>]+)>'
  )
  
  
  def _route_to_regex(route, is_endpoint=False):
      """
keep keep keep keep replace keep keep keep keep keep
 Fixed #31459 -- Fixed handling invalid indentifiers in URL path conversion.

This patch adjusted existing tests that used invalid identifiers. 
django/urls/resolvers.py