input: Write a python function to generate an array of 20 random integers between 1 and 100.
  assert len(generate_array()) == 20
  assert all(1 <= num <= 100 for num in generate_array())
  assert isinstance(generate_array(), list)
output: def generate_array():
      import random
      return [random.randint(1, 100) for _ in range(20)]