input: Write a function to generate a random number between 0 and 9. The function should return the random number as the output.
  assert generate_random_number()==5
  assert generate_random_number()==2
  assert generate_random_number()==8
  assert generate_random_number()==9
  assert generate_random_number()==1
output: import random
  
  def generate_random_number():
      return random.randint(0, 9)