arr1 = [9, 8, 9, 7, 8, 9, 6] #viewer problem like 2 slits problem
tripplets = []
for x in arr1:              # 1. num is fixed
    for a in range(1, 10):  # 2. num from 1..9
        for b in range(1, 10):  # 3. num from 1..9
            tripplets.append((x, a, b))
for t in tripplets:
    if t[0]==9 and t[2]==6 and (t[2]+t[1]==t[0]):
        print(t)
    if t[0]==6 and t[2]==9 and (t[2]+t[1]==t[0]):
        print(t)
    if t[1]==9 and t[2]==6 and (t[0]+t[1]==t[2]):
        print(t)
    if t[1]==6 and t[2]==9 and (t[0]+t[1]==t[2]):
        print(t)
    if t[2]==9 and t[0]==6 and (t[2]+t[0]==t[1]):
        print(t)
    if t[2]==6 and t[0]==9 and (t[2]+t[0]==t[1]):
        print(t)    

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