docs: function upload (res, file, showProgress = noOp, fn = uploadRequest) {
    return new Promise((resolve, reject) => {
      fn(res, file, showProgress)
        .then(responseStatus)
        .then(parseJSON)
        .then((res) => {
          resolve(res)
        })
        .catch((err) => {
          reject(err)
        })
    })
  }