compare method from GLib.DateTimes raises an error

See the following code. It fails with this message: Pointer arguments are restricted to integers, capsules, and None. See: https://bugzilla.gnome.org/show_bug.cgi?id=683599

pygobject 3.32.0

#!/usr/bin/env python3
 
from gi.repository import GLib
 
a = GLib.DateTime.new_now_utc()
b = GLib.DateTime.new_now_utc()
 
try:
 GLib.DateTime.compare(a, b)
except ValueError as e:
 # Pointer arguments are restricted to integers, capsules, and None.
 # See: https://bugzilla.gnome.org/show_bug.cgi?id=683599
 print("failed: ", e)