def clear_value(self, ctx):
        node_state = self._get_state(ctx)
        node_state.has_value = False
        node_state.value = None
        node_state.generator = None

        # clearing the value also marks the node as dirty
        self._set_dirty(node_state, DIRTY_FLAGS_ALL, 0)
clears any currently set value for this node
dataset/ETHPy150Open manahl/mdf/mdf/nodes.py/MDFNode.clear_value