title: why does python tell me that my yes variable not defined?
body: <p>I wrote this script with Python 2.7:</p>
  
  <pre><code>name=raw_input("Hi im a PC, who are you?")
  
  print("Hi " + name + " how are you, are you good?")
  
  answer = raw_input("")
  
  if (answer) == yes:
      print("That's good to hear")
  elif (answer) == no:
      print("Oh well")
  else:
      print("Sorry, you didnt answer the question properly, Please answer with a yes or no")
  </code></pre>
  
  <p>This is the error I get:</p>
  
  <pre>
  Traceback (most recent call last):
  
  File "C:/Python27/programs/2", line 4, in 
  
       if (answer) == yes:
  
  NameError: name 'yes' is not defined
  </pre>