Hello. This Thevenin theorem example. However, I know that first step should be turn off all independent sources which is current and voltage source in this circuit. Then find the Rth but the thing is I am confused by the 2 ohm resistor on the left side of terminal a. Why photo next shows that only one 2 ohms resistor to find Rth? Should it be eleminated because 2v voltage source is shorted?