type_hinting.py

type_hinting.py

def group_average(scores):
    """Compute the average score for each group.

    Args:
        scores: Records like {"group": str, "score": number}. Records with missing
            keys or invalid scores are ignored.

    Returns:
        Mapping from group name to average score.
    """
    totals = {}
    counts = {}

    for row in scores:
        group = row.get("group")
        if not group:
            continue
        try:
            score = float(row.get("score"))
        except (TypeError, ValueError):
            continue

        totals[group] = totals.get(group, 0.0) + score
        counts[group] = counts.get(group, 0) + 1

    return {g: totals[g] / counts[g] for g in totals}