def METHOD_NAME(post):
    post["date"] = text.parse_datetime(
        post["creationTime"], "%Y-%m-%dT%H:%M:%S.%fZ")
    tags = []
    append = tags.append
    tags_categories = collections.defaultdict(list)
    for tag in post["tags"]:
        tag_type = tag["category"].rpartition("_")[2]
        tag_name = tag["names"][0]
        tags_categories[tag_type].append(tag_name)
        append(tag_name)
    post["tags"] = tags
    for category, tags in tags_categories.items():
        post["tags_" + category] = tags