<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def contribute_to_class(self, cls, name):
 """Contribute the state to a Model. Attaches a StateFieldProperty to wrap the attribute. """

        super(StateField, self).contribute_to_class(cls, name)

        parent_property = getattr(cls, self.name, None)
        setattr(cls, self.name, StateFieldProperty(self, parent_property))