[array([1, 2, 7, 8, 9]), array([1, 2, 10, 11, 12]), array([3, 4, 7, 8, 9]),
    array([3, 4, 10, 11, 12]), array([5, 6, 7, 8, 9]), array([5, 6, 10, 11,
    12])]
Concatenation of every row combination of two numpy arrays