def read(self, *args, **kwargs):
"""Each object should implement read so it is easy to get the value of such object.
When you implement this method, the exact return value is up to you but it *MUST* be
consistent with what :py:meth:`fill` takes.
"""
raise DoNotReadThisWidget("Widget {} does not implement read()".format(type(self).__name__))
def do_not_read_this_widget():
"""Call inside widget's read method in case you don't want it to appear in the data."""
raise DoNotReadThisWidget('Do not read this widget.')
def read(self):
raise DoNotReadThisWidget()