components.py

class FirstComponent(object):
  def __init__(self, parent):
    object.__init__()
    parent.someFunc = self.someFunc

  def someFunc(self):
    return 42

class GameObject(object):
  def __init__(self):
    object.__init__()
    self._components = []
    component = FirstComponent(self)
    self._components.append(component)

if __name__ == "__main__":
  go = GameObject()
  if has_attr(go, "someFunc"):
    go.someFunc()
  # or
  try:
    go.someFunc()
  except:
    pass # nothing, it's just not implemented for this object