import random
random.seed(4)
lis = []
flag = False
msg_len = 30

a = random.randint(1,10)
b = random.randint(1,10)

lis.append([a,b])

while(len(lis)!=msg_len):
    a = random.randint(1,10)
    b = random.randint(1,10)
    if([a,b] not in lis):
        lis.append([a,b])

print(lis)