docs: def get_views_traffic(self, per=github.GithubObject.NotSet):
          """
          :calls: `GET /repos/:owner/:repo/traffic/views <https://developer.github.com/v3/repos/traffic/>`_
          :param per: string, must be one of day or week, day by default
          :rtype: None or list of :class:`github.View.View`
          """
          assert per is github.GithubObject.NotSet or (isinstance(per, (str, unicode)) and (per == "day" or per == "week")), "per must be day or week, day by default"
          url_parameters = dict()
          if per is not github.GithubObject.NotSet:
              url_parameters["per"] = per
          headers, data = self._requester.requestJsonAndCheck(
              "GET",
              self.url + "/traffic/views",
              parameters=url_parameters
          )
          if (isinstance(data, dict)) and ("views" in data) and (isinstance(data["views"], list)):
              data["views"] = [
                  github.View.View(self._requester, headers, item, completed=True)
                  for item in data["views"]
              ]
              return data