def get_prefix_from_proxy_group(proxy_group):
    """
    Return prefix by analyzing proxy_group name

    Args:
        proxy_group (str): proxy group name

    Returns:
        str: prefix if exists, empty string if not
    """
    split_name = proxy_group.split("@")[0].split("-")

    # if there's only two sections, there's no prefix
    if len(split_name) <= 2:
        return ""

    return proxy_group.split("@")[0].split("-")[-3].strip()