PyMOL>load dat/pept.pdb
 CmdLoad: "dat/pept.pdb" loaded as "pept".
PyMOL>select cas,name ca
 Selector: selection "cas" defined with 13 atoms.
PyMOL>set line_width,5
 Setting: line_width set to 5.00000.
PyMOL>show spheres,name n
PyMOL>save tmp/session.pse
 Save: Please wait -- writing session file...
 Save: wrote "tmp/session.pse".
PyMOL>reinitialize
PyMOL>print cmd.get_names()
[]
PyMOL>get line_width
 get: line_width = 1.49000
PyMOL>count_atoms rep spheres
 count_atoms: 0 atoms
PyMOL>load tmp/session.pse
 Executive: Loading version 1.20 session...
PyMOL>print cmd.get_names()
['pept']
PyMOL>get line_width
 get: line_width = 5.00000
PyMOL>count_atoms rep spheres
 count_atoms: 13 atoms
PyMOL>count_atoms cas
 count_atoms: 13 atoms
