input: Write a function to populate an array with random numbers from 1 to 100. The function should take an integer representing the length of the array as input.
  assert populateArray(5)==[random.randint(1, 100) for _ in range(5)]
  assert populateArray(0)==[]
  assert populateArray(1)==[random.randint(1, 100)]
output: import random
  
  def populateArray(length):
      return [random.randint(1, 100) for _ in range(length)]