      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 query parameter.")
 </s> add     invalid_version_message = _('Invalid version in query parameter.') </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_version_message = _("Invalid version in \"Accept\" header.")
 </s> add     invalid_version_message = _('Invalid version in "Accept" header.') </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
 prefer single quotes in source and double quotes in user visible strings; add some missing full stops to user visible strings 
rest_framework/versioning.py