for ( var i = 0; i < geometry.vertices.length; i ++ ) {

    // Imaginary functions to calculate the indices and weights
    // This part will need to be changed depending your skeleton and model
    var skinIndex = calculateSkinIndex( geometry.vertices, i );
    var skinWeight = calculateSkinWeight( geometry.vertices, i );

    // Ease between each bone
    geometry.skinIndices.push( new THREE.Vector4( skinIndex, skinIndex + 1, 0, 0 ) );
    geometry.skinWeights.push( new THREE.Vector4( 1 - skinWeight, skinWeight, 0, 0 ) );

}

mesh = bpy.data.meshes.new('Mesh')
mesh.from_pydata(self.verts, [], self.faces)
mesh_object = bpy.data.objects.new('Mesh_Object', mesh)
bpy.context.scene.objects.link(mesh_object)
# How to add in vertex weights and indices?