def remove_empty_kps(coco_context):
    """Returns a list of valid keypoint annotations

    Arguments:
        coco_context: The initialized cocoapi class

    Returns:
        processed_idx (list): List of images with
            valid keypoint annotations
    """
    processed_idx = []
    image_idx_list = coco_context.imgs.keys()
    for idx in image_idx_list:
        ann_ids = coco_context.getAnnIds(imgIds=idx)
        ann_dict = coco_context.loadAnns(ann_ids)
        if len(ann_dict) > 0:
            processed_idx.append(idx)
    return sorted(processed_idx)