from typing import Dict, List


def isrc_to_id_mapper(tracklist: List[Dict]):
    """
    Return isrc to track_id dictionary

    Args:
        tracklist (List[dict]): List of track data items.

    Returns:
         Dict
    """
    return {t["isrc"].upper(): t["id"] for t in tracklist if t["isrc"] and t["id"]}