Do not crash on *every* page load if there is no ToS Document.
'tos' ReferenceProperty might be present, but still be None.
Patch by: Todd Larsen
Review by: to-be-reviewed
# Until model subclassing is a possibility, a mixin class is used to add
# the necessary functions that may be contributed for geographic objects.
class GeoMixin:
"""
The Geographic Mixin class provides routines for geographic objects,
however, it is no longer necessary, since all of its previous functions
may now be accessed via the GeometryProxy. This mixin is only provided
for backwards-compatibility purposes, and will be eventually removed
(unless the need arises again).
"""
pass