drone_a = [10, 20, 35]
drone_b = [15, 25, 30]
target = 10
answer = []

for i in range(len(drone_a)):
    for j in range(i+1,len(drone_a)):
        if drone_a[i] - drone_b[j] == target or drone_b[j] - drone_a[i] == target:
            answer.append(drone_a[i])
            answer.append(drone_b[j])

print(answer)