old_contents: __author__ = 'sergey'
  
new_contents: __author__ = 'sergey'
  
  
  class AbstractDuck:
      def __init__(self, name):
          self.name = name
  
      def swim(self):
          print "I'm swimming"
  
  
  class Flying:
      def fly(self):
          print "I'm fly"
  
  
  
  
subject: comment #1