How to toggle a Boolean variable and then read the final value

Hello guys, I am working with a constraint model where I want to toggle a Boolean variable every once in a while and I also want to read the value of the Boolean variable using model runtime.

Python example of what I want to implement in a constraint program:

bool b1 = False
for i in range(5):
     if(i%2==0):
           bool = !bool

if(bool):
    print("It is true")

--------

end the model and return values of decision variable

Is there any way we can toggle a boolean variable in a constraint model and read it during Run time? Or any other way to achieve this using a constraint program?

I would really appreciate your help :)