move the ship

Scripting Issues
3

There is another way so the function does not need to be defined before it’s called. Make it a function in the class, and because it’s a class function then, you need to call it with self.subir. Like:

class World(DirectObject):
   def __init__(self):
      self.accept("escape",sys.exit)
      self.accept("s",self.subir)
   def subir(self):
      zeta = zeta + 1

Btw. your coding style is horrible this way. I suggest putting the rest also in the class constructor or don’t use classes at all.