If one of the traits of a CodeInputWidget instance is changed, the values are changed but the displayed widget is not updated. I assume that somewhere the traits are not correctly linked? Here is a small example
from widget_code_input import CodeInputWidget
wci = CodeInputWidget(function_name="foo", function_body="return 5")
wci
Then in another cell
wci.function_body = "return 6"
But the displayed function_body does not change. It is however registered as trait.