code: public Blob getBlobFromId(String bucketName, String blobName) {
      // [START getBlobFromId]
      BlobId blobId = BlobId.of(bucketName, blobName);
      Blob blob = storage.get(blobId);
      // [END getBlobFromId]
      return blob;
    }
docs: [VARIABLE "my_blob_name"]