Make internal edge elements (MESH)

Hello,
I am trying to create the missing elements (faces and edges) ie., internal elements of a mesh.
for the internal faces I successfully created them using:

Mesh_1.MakeBoundaryOfEachElement()

this will create face elements for each internal face.

but for the internal edges (ie., edges of this internal faces) I can not successfully create them (at least with a direct function), is this even possible? I tried the function
Mesh_1.MakeBoundaryElements(dimension=SMESH.BND_1DFROM3D) which WILL create edge elements but only on the surface of the model (CAD), as by default the mesh creates edge elements only in the edges of the CAD model.
so:
compute meshing-> edge elements on edges of CAD model, face elements on surfaces of CAD model
Mesh_1.MakeBoundaryOfEachElement()->face elements on the complete CAD model, so the volume of it (desired)
Mesh_1.MakeBoundaryElements(dimension=SMESH.BND_1DFROM3D)->edges elements on the surfaces of CAD model (desired)
still missing edge elements on the complete CAD model (the volume of it)

I also tried (without success):

facesIDs=Mesh.GetElementsByType( SMESH.FACE )

Mesh_1.MakeBoundaryMesh(facesIDs, dimension=SMESH.BND_1DFROM2D)

thanks in advance