1x = [[foo for i in range(10)] for j in range(10)]
2# x is now a 10x10 array of 'foo' (which can depend on i and j if you want)
3
1x = [[foo for i in range(10)] for j in range(10)]
2# x is now a 10x10 array of 'foo' (which can depend on i and j if you want)