input: Write a function to generate a random 6-digit number in Python. The function should return the generated number as an integer.
  
  assert generate_6_digit_number()!=generate_6_digit_number()
  assert generate_6_digit_number()>100000
  assert generate_6_digit_number()<999999
output: import random
  
  def generate_6_digit_number():
      return random.randint(100000, 999999)