code: def _mapped_populations(mdl1, mdl2):
      
      return_vect = np.zeros(mdl1.n_states_)
      for i in range(mdl1.n_states_):
          try:
              #there has to be a better way to do this
              mdl1_unmapped = mdl1.inverse_transform([i])[0][0]
              mdl2_mapped = mdl2.mapping_[mdl1_unmapped]
              return_vect[i] =  mdl2.populations_[mdl2_mapped]
          except:
              pass
      return return_vect
docs: Method to get the populations for states in mdl 1
      from populations inferred in mdl 2. Resorts to 0
      if population is not present.