old_contents: from challenge import Challenge
  import flask
  
  class c7(Challenge):
      '''
      Challenge 7
      Satoshi Base58 Encoding
      '''
  
      def __init__(self):
          super()
          self._id = 'a1adda29d338287fe42d20c1a7d6e32481129a9b'
          self._hints = {1: 'Base58 Encoding'}
  
      def get_response(self, app):
          return app.send_static_file('c7/index.html')
  
new_contents: from challenge import Challenge
  import flask
  
  class c7(Challenge):
      '''
      Challenge 7
      Satoshi Base58 Encoding
      '''
  
      def __init__(self):
          super()
          self._id = '3aed4348ed11e6adf1b54885b297078070ac455'
          self._hints = {1: 'Base58 Encoding'}
  
      def get_response(self, app):
          return app.send_static_file('c7/index.html')
  
subject: Fix incorrect challenge id