def allow(self, act, obj=None):
objc = obj.components if obj is not None else []<EOL>try:<EOL><INDENT>return self.tree[act.components + objc] == '<STR_LIT>'<EOL><DEDENT>except KeyError:<EOL><INDENT>return False<EOL><DEDENT>
Determine where a given action on a given object is allowed.