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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def transitions(self, omega_min=None, omega_max=None):
 r"""Find all allowed transitions. This function finds all allowed transitions (by electric-dipole selection rules) in the atom. 270 Arguments omega_min and omega_max can be used to make filter out the results. 780.241476935 85Rb 5S_1/2 -----> 85Rb 5P_3/2 776.157015322 85Rb 5P_3/2 -----> 85Rb 5D_3/2 775.978619616 85Rb 5P_3/2 -----> 85Rb 5D_5/2 """

        states = self.states()
        transitions = states
        transitions = []
        for i in range(len(states)):
            si = states[i]
            for j in range(i):
                sj = states[j]
                t = Transition(sj, si)
                if t.allowed:
                    transitions += [t]

        if omega_min is not None:
            transitions = [ti for ti in transitions
                           if abs(ti.omega) >= omega_min]
        if omega_max is not None:
            transitions = [ti for ti in transitions
                           if abs(ti.omega) <= omega_max]

        return transitions