Called when an instance is updated through a call to .set()
(or a column attribute assignment). The arguments are
(instance, post_funcs). post_funcs is a list of callbacks,
intended to have functions appended to it, and are called with the
arguments (new_instance). This is run after the instance is
updated; Works better with lazyUpdate = True.
The RowUpdatedSignal class is accessible via the
__sizeof__() -> int
size of object in memory, in bytes
Abstract classes can override this to customize issubclass().
This is invoked early on by abc.ABCMeta.__subclasscheck__().
It should return True, False or NotImplemented. If it returns
NotImplemented, the normal algorithm is used. Otherwise, it
overrides the normal algorithm (and the outcome is cached).
x.__init__(...) initializes x; see help(type(x)) for signature
for more information.