text: from autode.pes import min_energy_pathway as mep
  from autode.pes.pes_2d import PES2d
  from autode.species.complex import ReactantComplex, ProductComplex
  from autode.species.molecule import Molecule
  from copy import deepcopy
  import numpy as np
  
  
  def test_sum_mep():
      reactant = ReactantComplex(Molecule(smiles='C', charge=0, mult=1))
      product = ProductComplex(Molecule(smiles='C', charge=0, mult=1))
      product.graph.remove_edge(0, 1)
      product.graph.remove_edge(0, 2)
  
      # Fictitious PES
      pes = PES2d(reactant, product,
                  r1s=np.linspace(1, 2, 3), r1_idxs=(0, 1),
                  r2s=np.linspace(1, 2, 3), r2_idxs=(0, 2))
  
      # Energies are all 0 apart from at the 'saddle point' (1, 1)
      for i in range(3):
          for j in range(3):
              pes.species[i, j] = deepcopy(reactant)
              pes.species[i, j].energy = 0
  
              if i == j == 2:
                  pes.species[i, j].graph = product.graph
  
      pes.species[1, 1].energy = 1
      mep_sum = mep.get_sum_energy_mep(saddle_point_r1r2=(1.5, 1.5), pes_2d=pes)
  
      # Energy over the saddle point is 1 both sides -> 2 Ha
      assert mep_sum == 2
  