def is_magic_5gon_ring(elements):
    """
    Return True if elements (10-vector) form a "magic" ring
    """
    total = sum(elements[0:3])
    return sum(elements[2:5]) == total and sum(elements[4:7]) == total \
        and sum(elements[6:9]) == total and elements[1] + sum(elements[8:10]) == total