import openmesh as om
import numpy as np

mesh = om.TriMesh()

# add a a couple of vertices to the mesh
vh0 = mesh.add_vertex([0, 1, 0])
vh1 = mesh.add_vertex([1, 0, 0])
vh2 = mesh.add_vertex([2, 1, 0])
vh3 = mesh.add_vertex([0,-1, 0])
vh4 = mesh.add_vertex([2,-1, 0])

# add a couple of faces to the mesh
fh0 = mesh.add_face(vh0, vh1, vh2)
fh1 = mesh.add_face(vh1, vh3, vh4)
fh2 = mesh.add_face(vh0, vh3, vh1)

# add another face to the mesh, this time using a list
vh_list = [vh2, vh1, vh4]
fh3 = mesh.add_face(vh_list)

#  0 ==== 2
#  |\  0 /|
#  | \  / |
#  |2  1 3|
#  | /  \ |
#  |/  1 \|
#  3 ==== 4

# get the point with vertex handle vh0
point = mesh.point(vh0)

# get all points of the mesh
point_array = mesh.points()

# translate the mesh along the x-axis
point_array += np.array([1, 0, 0])

# write and read meshes
om.write_mesh('test.off', mesh)
mesh_2 = om.read_trimesh('test.off')

pip install openmesh

conda install -c conda-forge openmesh-python