docs: def match_urls_to_resources(self, url_values):
          """
          For the list of valid URLs, try and match them up
          to resources in the related_resources attribute.
  
          Args:
              url_values: A dictionary of keys and URL strings that
                          could be related resources.
          Returns:
              valid_values: The values that are valid
          """
          valid_values = {}
          for resource in self.Meta.related_resources:
              for k, v in url_values.items():
                  resource_url = resource.get_resource_url(
                      resource, resource.Meta.base_url)
                  if isinstance(v, list):
                      if all([resource_url in i for i in v]):
                          self.set_related_method(resource, v)
                          valid_values[k] = v
                  elif resource_url in v:
                      self.set_related_method(resource, v)
                      valid_values[k] = v
          return valid_values