old_contents: 
  import mimpy.mesh.hexmesh as hexmesh
  import mimpy.mesh.mesh as mesh
  import numpy as np
  
  
  import unittest
  
  class TestCellDivide(unittest.TestCase):
      
      def test_write(self):
          two_cells = hexmesh.HexMesh()
          two_cells.build_mesh(2, 3, 2, 
                               lambda x, i, j,
                               1., 1., 1.,
                               k: np.eye(3))
  
          two_cells.build_frac_from_faces([5])
          
          output_file = open("test_output", 'w')
          two_cells.save_mesh(output_file)
          output_file.close()
  
          input_file = open("test_output")
  
          loaded_mesh = mesh.Mesh()
          
          loaded_mesh.load_mesh(input_file)
          
          assert(two_cells.get_number_of_faces() ==
                 loaded_mesh.get_number_of_faces())
  
          assert(two_cells.get_number_of_cells() ==
                 loaded_mesh.get_number_of_cells())
          
  
      def test_write_single(self):
          two_cells = hexmesh.HexMesh()
          two_cells.build_mesh(2, 2, 2, 
                               lambda x, i, j,
                               1., 1., 1.,
                               k: np.eye(3))
  
          two_cells.build_frac_from_faces([5])
          
          output_file = open("test_output", 'w')
          two_cells.save_mesh(output_file)
          output_file.close()
  
          input_file = open("test_output")
  
          loaded_mesh = mesh.Mesh()
          
          loaded_mesh.load_mesh(input_file)
          
          assert(two_cells.get_number_of_faces() ==
                 loaded_mesh.get_number_of_faces())
  
          assert(two_cells.get_number_of_cells() ==
                 loaded_mesh.get_number_of_cells())
          
          
          
          
          
          
  
new_contents: 
  import mimpy.mesh.hexmesh as hexmesh
  import mimpy.mesh.mesh as mesh
  import numpy as np
  
  
  import unittest
  
  class TestCellDivide(unittest.TestCase):
      
      def test_write(self):
          two_cells = hexmesh.HexMesh()
          two_cells.build_mesh(2, 3, 2, 
                               1., 1., 1.,
                               lambda x, i, j, k: np.eye(3))
  
          two_cells.build_frac_from_faces([5])
          
          output_file = open("test_output", 'w')
          two_cells.save_mesh(output_file)
          output_file.close()
  
          input_file = open("test_output")
  
          loaded_mesh = mesh.Mesh()
          
          loaded_mesh.load_mesh(input_file)
          
          assert(two_cells.get_number_of_faces() ==
                 loaded_mesh.get_number_of_faces())
  
          assert(two_cells.get_number_of_cells() ==
                 loaded_mesh.get_number_of_cells())
          
  
      def test_write_single(self):
          two_cells = hexmesh.HexMesh()
          two_cells.build_mesh(2, 2, 2, 
                               lambda x, i, j,
                               1., 1., 1.,
                               k: np.eye(3))
  
          two_cells.build_frac_from_faces([5])
          
          output_file = open("test_output", 'w')
          two_cells.save_mesh(output_file)
          output_file.close()
  
          input_file = open("test_output")
  
          loaded_mesh = mesh.Mesh()
          
          loaded_mesh.load_mesh(input_file)
          
          assert(two_cells.get_number_of_faces() ==
                 loaded_mesh.get_number_of_faces())
  
          assert(two_cells.get_number_of_cells() ==
                 loaded_mesh.get_number_of_cells())
          
          
          
          
          
          
  
subject: Update test_read_write.py