A function used by gtk.tree_selection.TreeSelection.setSelectFunction to filter
whether or not a row may be selected. It is called whenever a row's
state might change. A return value of true indicates to selection
that it is okay to change the selection.
A function used by gtk.tree_selection.TreeSelection.setSelectFunction to filter whether or not a row may be selected. It is called whenever a row's state might change. A return value of true indicates to selection that it is okay to change the selection.