code: def negotiate_forced_aspect(self, options, accepts):
          
          if not options:
              return None
  
          priorities = {}
  
          for i, o in enumerate(options):
              p = accepts.get(o, None)
              if p is None:
                  p = accepts.get("*", None)
              if p is not None:
                  # Prevent that a priority of 0 mess with the order of options
                  priorities[o] = max(p, 0.000001) * (1 - i * 0.1 / len(options))
  
          if not priorities:
              return None
  
          order = priorities.keys()
          order.sort(key=priorities.get)
          return order[::-1]
docs: Order specified options in function of the specified
          accept priorities.