def stateLabel(s, state_type):
        """Returns the short-hand label of the state.
        
        Parameters:
            s (State): a State object.
            state_type (string): either 'e' or 'g' for excited state or ground state. The ground state is primed.
            
        Returns:
            string: "J=k;m_J=l" if k and l are J and m quantum numbers. If the state has isospin then it is "F=k;m_F=l"
        """
        
        if(s.I != None):
            letter = "F"
        else:
            letter = "J"
        
        if(state_type == "g"):  # Prime the letter if a ground state
            letter += "'"
            
        return f"{letter}={s.F};m_{letter}={s.m}"