NotImplementedError is the name of the exception (https://docs.python.org/2/library/exceptions.html). NotImplemented is the name of a constant (https://docs.python.org/2/library/constants.html). >>> raise NotImplemented() Traceback (most recent call last): File "<pyshell#31>", line 1, in <module> raise NotImplemented() TypeError: 'NotImplementedType' object is not callable >>> raise NotImplementedError() Traceback (most recent call last): File "<pyshell#32>", line 1, in <module> raise NotImplementedError() NotImplementedError This patch fix it. Change-Id: Ia8bf7d75cd7f70e503b9669fc60ea9d89642489b Closes-Bug: #1339855