code: async function _getPresignedPosts(siteId, checksums) {
    const endpoint = url.resolve(apiURL, `/sites/${siteId}/presigned_posts`);
    const body = { checksums };
    const response = await got.post(endpoint, { body, json: true, headers: _bearer() });
  
    return response.body.presignedPosts;
  }
docs: Gets presigned posts
  
  @param {string} siteId
  @param {Object} checksums
  @return {Object}