code: function(options, callback) {
      return WebApiRequest.builder(this.getAccessToken())
        .withPath('/v1/me/player/repeat')
        .withQueryParameters({
          state: options.state || 'off'
        })
        .build()
        .execute(HttpManager.put, callback);
    }
docs: Set Repeat Mode On The Current User's Playback
  @param {Object} [options] Options, being state (track, context, off).
  @param {requestCallback} [callback] Optional callback method to be called instead of the promise.
  @example playbackRepeat({state: 'context'}).then(...)
  @returns {Promise|undefined} A promise that if successful, resolves into a paging object of tracks,
  otherwise an error. Not returned if a callback is given.