      Host: v1.example.com
      Accept: application/json
      """
      hostname_regex = re.compile(r'^([a-zA-Z0-9]+)\.[a-zA-Z0-9]+\.[a-zA-Z0-9]+$')
      invalid_version_message = _('Invalid version in hostname.')
  
      def determine_version(self, request, *args, **kwargs):
          hostname, seperator, port = request.get_host().partition(':')
          match = self.hostname_regex.match(hostname)
          if not match:
 
</s> remove     invalid_version_message = _('Invalid version in URL path.')
 </s> add     invalid_version_message = _("Invalid version in URL path.") </s> remove     invalid_version_message = _('Invalid version in URL path.')
 </s> add     invalid_version_message = _("Invalid version in URL path.") </s> remove         'invalid': _('This value does not match the required pattern.')
 </s> add         'invalid': _("This value does not match the required pattern.") </s> remove         'invalid': _('Invalid value.'),
 </s> add         'invalid': _("Invalid value."), </s> remove     default_detail = _('Request was throttled.')
    extra_detail_singular = 'Expected available in {wait} second.'
    extra_detail_plural = 'Expected available in {wait} seconds.'
 </s> add     default_detail = _("Request was throttled.")
    extra_detail_singular = "Expected available in {wait} second."
    extra_detail_plural = "Expected available in {wait} seconds."
    invalid_version_message = _("Invalid version in hostname.")
      Host: v1.example.com
      Accept: application/json
      """
      hostname_regex = re.compile(r'^([a-zA-Z0-9]+)\.[a-zA-Z0-9]+\.[a-zA-Z0-9]+$')
    invalid_version_message = _("Invalid version in hostname.")
  
      def determine_version(self, request, *args, **kwargs):
          hostname, seperator, port = request.get_host().partition(':')
          match = self.hostname_regex.match(hostname)
          if not match:
keep keep keep keep replace keep keep keep keep keep
 use double quotes for user visible strings; end user visible strings in full stops; add some missing translation tags 
rest_framework/versioning.py