To create a Shell in the Main Menu select New Entity - > Build - > Shell
You can create a Shell from a list of faces and (or) shells.
The Result will be a GEOM_Object (SHELL).
TUI Command: geompy.MakeShell(ListOfShape)
Arguments: Name + List of faces having connected edges.
Example:
Our TUI Scripts provide you with useful examples of creation of Advanced Geometric Objects.