Hi Beamers! I was working in some code samples and noticed that side inputs are not working in CombineGlobally in the Python SDK.
If I use an beam.pvalue.AsSingleton() side input, the variable is of type AsSingleton instead of the actual data type of the element in the PCollection. Same happens with other side inputs like AsIter. I filed BEAM-8400 <https://issues.apache.org/jira/browse/BEAM-8400> to track this issue. Here's a Colab notebook <https://colab.research.google.com/drive/149By0ZKJjb_JdDOsFywdT_OLj1hMEPBa> to reproduce the issue. It's failing in the latest pypi version 2.16.0, but it also fails in the latest master (0b415fd7e9dd5c80034ca237e08c3959ec78ffe3 as of writing this)
