input: Write a python function to generate a matrix of given length with random integers between 0 and 100.
  assert len(generate_matrix(3)) == 3 and all(len(row) == 3 for row in generate_matrix(3))
  assert len(generate_matrix(5)) == 5 and all(len(row) == 5 for row in generate_matrix(5))
  assert all(0 <= num <= 100 for row in generate_matrix(4) for num in row)
output: import random
  
  def generate_matrix(n):
      return [[random.randint(0, 100) for _ in range(n)] for _ in range(n)]