how to declare 2d array in python size code example

Example 1: python initialize a 2d array

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

Example 2: python initialize a 2d array

bar = [SOME EXPRESSION for item in some_iterable]