NAME
	environment - find the environment of an object

SYNOPSIS
	object environment(object ob)

DESCRIPTION
	This function returns the object that has `ob' in its inventory, 
	the environment of `ob'. If no object is given as argument,
	`this_object()' is used by default.
	If no environment to `ob' is found, 0 is returned.

SEE ALSO
	all_inventory, deep_inventory, first_inventory, next_inventory