<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def find_decays(self, fine_state):
 r"""Find all possible decays from a given fine state. This function finds all the states to which a given fine structure state can decay (through electric dipole selection rules). [133Cs 6P_3/2, 133Cs 6S_1/2] [133Cs 6D_5/2, 133Cs 6P_3/2, 133Cs 7P_3/2, 133Cs 6S_1/2, 133Cs 5D_3/2, 133Cs 5D_5/2, 133Cs 7S_1/2, 133Cs 6P_1/2] """

        def decays_from(fine_state, transitions):
            states_below = []
            for t in transitions:
                if t.e2 == fine_state:
                    states_below += [t.e1]
            return states_below

        def iterate(states, transitions):
            new_and_old_states = states[:]
            for state in states:
                new_states = decays_from(state, transitions)
                for new_state in new_states:
                    if new_state not in new_and_old_states:
                        new_and_old_states += [new_state]

            if states == new_and_old_states:
                return states
            else:
                return iterate(new_and_old_states, transitions)

        transitions = self.transitions()
        states = iterate([fine_state], transitions)

        return states