Sagemaker pipeline: can step_c depend on step_a OR step_b?

[fishsauceineverything]

I have a situation in sagemaker pipeline where depending on some condition, step_a and step_b will have different input but they output to the same location. Only one of them will get executed in the pipeline run. As long as either of them finished, step_c can start.
I looked through examples and docs, seems like if I dostep_c.depend_on([step_a, step_b]), it will wait for both step_a and step_b, but I want it to depend on a OR b. Is it possible today?