title: Calling a class method from another class method in Python 2.7
body: <p>I'm confused why this code won't work.  For <code>room_instance = self.startRoom()</code> I get the error: </p>
  
  <pre><code>'str' object is not callable.  
  </code></pre>
  
  <p><strong>My code:</strong></p>
  
  <pre><code>class Corridor:
      def enter(self):
          print "Yureka. First Room!"
  
  class Engine(object):
      def __init__(self, startRoom):
          self.startRoom = startRoom   #sets the startRoom to 'Corridor' for the eng instance
      def room_change(self):
          room_instance = self.startRoom()
          room_instance.enter()
  
  eng = Engine('Corridor')
  eng.room_change()
  </code></pre>