setting is the name of a JyMol setting.
selection can either be empty for getting global settings or a name-pattern-list or atom selection covering the objects whose settings are to be returned.
state is the state number (default 0).
returns the background color as a float with 3 numbers RGB.
returns the mouse selection mode as an integer (since this mode is stored in PyMOL as an integer which refer to selection modes: Atoms(0), Residues(1), Chains(2), Segments(3), Objects(4), Molecules(5), and C-alphas(6)).