Update examples/loom2parquetmerge.py

Co-authored-by: codiumai-pr-agent-pro[bot] <151058649+codiumai-pr-agent-pro[bot]@users.noreply.github.com>

examples/loom2parquetmerge.py

@@ -28,7 +28,7 @@ def concatenate_parquet_files_incremental(files_paths, output_path, batch_size=1
     :param batch_size: Number of rows to read from each file at a time.
     """
     writer = None
-
+with pq.ParquetWriter(output_path, schema=None, compression='gzip') as writer:
     for file_path in files_paths:
         print(f"Processing file: {file_path}")
         parquet_file = pq.ParquetFile(file_path)
@@ -38,16 +38,10 @@ def concatenate_parquet_files_incremental(files_paths, output_path, batch_size=1
             # Convert the batch to a PyArrow Table
             table = pa.Table.from_batches([batch])
 
-            # If the writer is not initialized, create a new Parquet writer
-            if writer is None:
-                writer = pq.ParquetWriter(output_path, table.schema, compression='gzip')
-
             # Write the batch to the output Parquet file
             writer.write_table(table)
 
-    # Close the writer after all batches are written
-    if writer is not None:
-        writer.close()
+print(f"Concatenated parquet file written to {output_path}")
         print(f"Concatenated parquet file written to {output_path}")