Summary:
I'm using Python ops in a project and need corresponding Python gradient ops. For my use case, only a subset of the forward op outputs have gradients and only a subset of forward op inputs have gradients. However the current implementation of `GetPythonGradient` forces all grad inputs and outputs to exist. This diff allows one to specify that only a subset of grad inputs / outputs are used when constructing the Python op.
I'm not sure if this is up to caffe2 standards, so please push back on style and content as needed.
Reviewed By: dzhulgakov
Differential Revision: D4897004
fbshipit-source-id: 96fffe8634c51a49b6bce7339a46c6235f7d4bbd
Summary:
DPER has very strange python ops that play with Workspace - they are somewhat similar to LoadOp/SaveOp, so I guess the semantics is fine.
Thus it makes sense to allow python operators to receive workspace pointer similarly to regular Operators.
I didn't figure out a better way to implement optional argument than just checking the number of args function receives on python side.
Reviewed By: ajtulloch
Differential Revision: D4242943
fbshipit-source-id: d97d4227815b741c8f884cfe254b06d2b56b5a41
