code: public Stream create(String streamKey) throws PiliException {
          String path = this.baseUrl + "/streams";
          CreateArgs args = new CreateArgs(streamKey);
          String json = gson.toJson(args);
  
          try {
              cli.callWithJson(path, json);
              StreamInfo streamInfo = new StreamInfo(hub, streamKey);
              return new Stream(streamInfo, cli);
          } catch (PiliException e) {
              throw e;
          } catch (Exception e) {
              throw new PiliException(e);
          }
      }
docs: create stream
  
  @param streamKey
  @return
  @throws PiliException