python3 jsonl-fields <input_file>
This tool loads the supplied JSONL file into memory, and emits a CSV-formatted content to standard output consisting of the profileId and any note fields for each record.
Note that for extremely large JSONL files, the current implementation may not work if it does not all fit into memory. A future extension could handle larger files if needed.
A message summarizing the total number of records processed is output to standard error.