## Given an input object that is a function, generate a string of the
    # form
    # "__pyrelFunctionPointer__:object ID:function name".
    def makeFunctionString(self, obj):
        # The im_self field on functions contains the object the function
        # is bound to.
        obj = key.im_self
        if not hasattr(obj, 'id'):
            # We can only serialize functions if they are bound to objects
            # that we are also serializing.
            raise RuntimeError("Tried to serialize a function bound to an object with no ID: %s" % str(obj))
        boundId = obj.id
        if boundId not in self.objectToId:
            # Unrecognized object ID.             raise RuntimeError("Tried to serialize a function bound to object with unknown ID %s" % boundID)
        ## The __name__ field is the function's name in string form.
        funcName = obj.__name__
        return "__pyrelFunctionPointer:%s:%s" % (boundId, funcName)