input: Below is an instruction that describes a task. Write a response that appropriately completes the request.
  
  ### Instruction:
  Create a function to generate a unique 6 digit number.
  
  ### Input:
  
  
  ### Output:
  import random 
  def generate_number(): 
        
      # Choose a random number 
      # between 10000 and 99999 
      random_number = random.randint(10000, 99999) 
    
      # Return the random number 
      return random_number 
    
  # Test cases
  """
  >>> generate_number()
  12345
  >>> generate_number()
  98765
  >>> generate_number()
  54321
  """
output:     return random_number