This cool project was developed by a teacher known as Jan K. S. on GitHub. It's an interactive visual interface built on top of gpiozero using TkInter to simulate wiring and programming Raspberry Pi components. This project proved useful for Jan's students who haven't been able to complete lab work in person due to the coronavirus.
The device simulator was built in TkInter using MockFactory, a library of mock pins used by gpiozero. The tools proved to be the perfect asset for constructing a user-friendly GUI for the students to learn with.
The library provides a wide selection of components to interface with. There are simple things like LEDs and more advanced modules like sensors. You can even take advantage of a few robotics kits.
The buttons in TkInter respond just like real, physical buttons would. You can use them to control virtual LEDs or any other component—including a simulated distance sensor.
According to Jan, there are plans to open source the project in the future after refining the code. In the meantime, you can check out the GitHub thread detailing the interface. Be sure to follow Jan K. S. on GitHub for future project updates.