How to use the meshplex.mesh_tri function in meshplex

# Define mesh attributes on root processor
        t0 = clock()
        t = clock()
        gpoints = np.zeros(1)
        if MPIrank == 0:
            cells = np.asarray(self.mdata.cells['triangle'], dtype=np.int32)
            coords = np.asarray(self.mdata.points, dtype=np.double)
            MPIcomm.bcast(cells.shape, root=0)
            MPIcomm.bcast(coords.shape, root=0)
            elev = self.mdata.point_data[filename[1]]
            gpoints[0] = len(coords)
            if self.verbose:
                print('Extract information (%0.02f seconds)'% (clock() - t))
            t = clock()
            Gmesh = meshplex.mesh_tri.MeshTri(coords, cells)
            if self.verbose:
                print('Reading meshplex meshtri (%0.02f seconds)'% (clock() - t))
            t = clock()
            Gmesh.mark_boundary()
            if self.verbose:
                print('Mark boundary TIN (%0.02f seconds)'% (clock() - t))
            ids = np.arange(0, len(Gmesh.node_coords), dtype=int)
            self.boundGlob = ids[Gmesh._is_boundary_node]
            t = clock()
            Gmesh.create_edges()
            if self.verbose:
                print('Defining edges TIN (%0.02f seconds)'% (clock() - t))
            t = clock()
            self.Gmesh_ngbNbs, self.Gmesh_ngbID = defineGTIN(gpoints[0], Gmesh.cells['nodes'], Gmesh.edges['nodes'])
            if self.verbose:
                print('Defining global TIN (%0.02f seconds)'% (clock() - t))

def _main():
    points = numpy.array([[0.0, 0.0], [1.0, 0.0], [0.3, 0.8]])
    # points = numpy.array([[0.0, 0.0], [1.0, 0.0], [0.5, numpy.sqrt(3) / 2]])
    cells = numpy.array([[0, 1, 2]])

    mesh = meshplex.mesh_tri.MeshTri(points, cells)

    lw = 5.0
    col = "0.6"

    ax = plt.gca()

    # circumcircle
    circle1 = plt.Circle(
        mesh.cell_circumcenters[0],
        mesh.circumradius[0],
        color=col,
        fill=False,
        linewidth=lw,
    )
    ax.add_artist(circle1)

# Define local vertex & cells
        t = clock()
        cStart, cEnd = self.dm.getHeightStratum(0)
        # Dealing with triangular cells only
        self.lcells = np.zeros((cEnd-cStart,3), dtype=PETSc.IntType)
        for c in range(cStart, cEnd):
            point_closure = self.dm.getTransitiveClosure(c)[0]
            self.lcells[c,:] = point_closure[-3:]-cEnd
        del point_closure
        if MPIrank == 0 and self.verbose:
            print('Defining local DMPlex (%0.02f seconds)'% (clock() - t))

        # Create mesh structure with meshplex
        t = clock()
        # Define mesh characteristics
        Tmesh = meshplex.mesh_tri.MeshTri(self.lcoords, self.lcells)
        self.FVmesh_area = np.abs(Tmesh.control_volumes)
        self.FVmesh_area[np.isnan(self.FVmesh_area)] = 1.
        self.boundary, self.localboundIDs = self._get_boundary()
        self.gbds = self.boundary.astype(int)

        # Voronoi and simplices declaration
        coords = Tmesh.node_coords
        Tmesh.create_edges()
        cc = Tmesh.cell_circumcenters
        edges_nodes = Tmesh.edges['nodes']
        cells_nodes = Tmesh.cells['nodes']
        cells_edges = Tmesh.cells['edges']

        if MPIrank == 0 and self.verbose:
            print('Voronoi creation (%0.02f seconds)'% (clock() - t))