code: function uriToBlob(uri, done) {
    const xhr = new XMLHttpRequest();
    xhr.responseType = "blob";
    xhr.onload = () => {
      const blob = xhr.response;
      done(null, blob);
    };
    xhr.onerror = (err) => {
      done(err);
    };
    xhr.open("GET", uri);
    xhr.send();
  }
docs: uriToBlob resolves a URI to a Blob object. This is used for
  React Native to retrieve a file (identified by a file://
  URI) as a blob.