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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def cross_section(verts, tris, plane_orig, plane_normal, **kwargs):
 """ Compute the planar cross section of a mesh. This returns a set of polylines. Args: verts: Nx3 array of the vertices position faces: Nx3 array of the faces, containing vertex indices plane_orig: 3-vector indicating the plane origin plane_normal: 3-vector indicating the plane normal Returns: A list of Nx3 arrays, each representing a disconnected portion of the cross section as a polyline """

    mesh = TriangleMesh(verts, tris)
    plane = Plane(plane_orig, plane_normal)
    return cross_section_mesh(mesh, plane, **kwargs)