title: While loop with if/elif/else statement
body: <p>I have just started learning Python and I have some issues with the while loop.</p>
  
  <pre><code>instruction_yes_no = ""
  
  while instruction_yes_no.lower() != "y" or "n":
      instruction_yes_no = input("Do you want to see the instruction? Please write 'Y' or 'N'\n")
      if instruction_yes_no.lower() == "y":
          print("You are gonna lose even if you read the instructions...")
          print("\n")
          time.sleep(1)
          instruction()
      elif instruction_yes_no.lower() == "n":
          print("Do you think you are better than me? I will beat you faster since you have not read the instructions")
          time.sleep(1)
      else:
          print("You mortal...you have not chosen a valid input. Type or 'Y' or 'N'")
          time.sleep(1)
      break
  </code></pre>
  
  <p>Basically I would like to obtain the following:</p>
  
  <p>1) If the user inputs 'y', the instruction() function is called (THIS WORKS)</p>
  
  <p>2) If the user inputs 'n', it prints ""Do you think you are better than me?..." (THIS WORKS)</p>
  
  <p>3) If the user does not type either 'y' or 'n', I would like to keep looping until the user insert or 'y' or 'n'.
  HOWEVER this is not working.</p>
  
  <p>I am not understanding why. This is how I think it should work:</p>
  
  <ul>
  <li><p>At the beginning the variable instruction_yes_no is set to ""</p></li>
  <li><p>It enter the loop because instruction_yes_no != than 'y' or 'n'</p></li>
  <li><p>Now, instruction_yes_no assumes the value that the user inputs</p></li>
  <li><p>If the user does not input either 'y' or 'n' it should keep looping, but is does not.</p></li>
  </ul>