creating a list from lists of lists

[ridgerunnersjw]

Can someone tell me how to sum values across lists of lists....For example I have a list of a list that is 2x4....It in turn is contained in a list that is 5 long so effectively a 2x4x5...I would like to grab the x element in each list from the whole 2x4x5...looking for the solution OTHER than numpy....Thank you...Here is the code for matrix list

Thank you!

#!/usr/bin/env python3
 2 import random
 3 def main():
 4     d = []
 5     for j in range(5):
 6         d.append([[random.randint(0,4) for i in range(4)] for k in range(2)])
 7     return(d)