def get_service_value(v, s, c):
    """Get service value.

    Returns a specified value from a
    given Portainer service.

    Args:
        v: Key for the service value
        s: Portainer service name
        c: Lisf of containers
    Returns:
        Service value.

    """
    return list(map(lambda x: x[v], filter(lambda x: x['service_name'] == s, c)))[0]