input: Write a python function to generate a multiplication table.
  assert generate_multiplication_table(3) == [[1, 2, 3], [2, 4, 6], [3, 6, 9]]
  assert generate_multiplication_table(4) == [[1, 2, 3, 4], [2, 4, 6, 8], [3, 6, 9, 12], [4, 8, 12, 16]]
  assert generate_multiplication_table(1) == [[1]]
output: def generate_multiplication_table(n):
      return [[(i + 1) * (j + 1) for j in range(n)] for i in range(n)]