[Bf-python] BMesh join

[Bence Liszkai]

Hi everyone,
I'm new to blender python scripting, so it might be a stupid question:
if i have more bmesh object, how can i join them into one? I can't
find any function for this.
I have try it manually with a for cycle, face by face, but it doesn't works:
b.faces.new(a.faces[i])    #a and b are BMesh objects
Is there a way to do this?

Thansk:
Liszi
(sorry for my english, it not the best...)