Hi,
Python examples for Aggregate transformer - CombineGlobally and CombiePerKey doesn't work for side inputs (singleton, iter and dict). Even when used with custom class inheriting beam.CombineFn it fails.
Third combine transformer - i.e., CombineValues is working fine without any issue.
Steps to recreate problem:
Python version 3.7.3
Apache beam = 2.24.0 (installed with gcp data flow components)
Imported from Jira BEAM-11185. Original Jira may contain additional context.
Reported by: aravindh.venkatesh.