def get_usage_data_labels(usage_data):
    """Return dict with human readable labels for each of the groups in each of the given usage data timeframes."""
    labels = {}
    timeframe_formats = {"day": "%H", "week": "%b %d", "month": "%b %d", "year": "%b %Y"}

    for timeframe, timeframe_data in usage_data.items():
        labels[timeframe] = [group["datetime"].strftime(timeframe_formats[timeframe]) for group in timeframe_data]

    # Modify hourly labels to signify that it is covering a period of an hour.
    labels["day"] = [f"{label}:00-{int(label) + 1:02}:00" for label in labels["day"]]

    return labels