Напишите программу, которая заполняет две матрицы случайными целыми числами, складывает матрицы и печатает

import random

def matrixGenerator(rows, cols):
    mainArray = range(rows) #number of rows of your matrix
    for i in range(rows):
        rowArray = range(cols)
    for ii in range(cols):
        rowArray[ii] = randNumber()
        mainArray[i] = rowArray
    return mainArray

def sumMatrices(matrix1, matrix2):
#the function assumes that both matrices are of the same size
    sumOfMatx = range(len(matrix1))
    rowsIndex = 0
    while rowsIndex < len(matrix1):
        matCol = range(len(matrix1[rowsIndex]))
        colsIndex = 0
    while colsIndex < len(matCol):
        matCol[colsIndex] = matrix1[rowsIndex][colsIndex] + matrix2[rowsIndex][colsIndex]
        colsIndex += 1
        sumOfMatx[rowsIndex] = matCol
        rowsIndex += 1
    return sumOfMatx

def printMat(matrix):
    for i in matrix:
        print(i)

def randNumber():
    return random.randint(1, 65323)

myMatrix1 = matrixGenerator(5, 5)
myMatrix2 = matrixGenerator(5, 5)
myMatrix3 = sumMatrices(myMatrix1, myMatrix2)

print("First matrix:")
printMat(myMatrix1)
print("\n")
print("Second matrix:")
printMat(myMatrix2)
print("\n")
print("Third matrix:")
printMat(myMatrix3)
print("\n")

Traceback (most recent call last):
  File "C:\Users\Катя\Desktop\123.py", line 39, in <module>
    myMatrix1 = matrixGenerator(5, 5)
  File "C:\Users\Катя\Desktop\123.py", line 14, in matrixGenerator
    rowArray[ii] = randNumber()
TypeError: 'range' object does not support item assignment