'Produce the value as it should be serialized.
Sometimes it is desirable for the serialized value to differ from
the ``__get__`` in order for the ``__get__`` value to appear simpler
for user or developer convenience.
Args:
obj (HasProps) : the object to get the serialized attribute for
Returns:
JSON-like'

def serializable_value(self, obj):

    value = self.__get__(obj, obj.__class__)
    return self.property.serialize_value(value)
