[Bug]: Python experiments and dataflow_service_options do not handle comma separated options

[Abacn]

What happened?

In Beam Java SDK, one can add experiments --experiments=abc,def, --dataflowServiceOptions=abc=true,def=true, but in Python SDK, --experiments=abc,def will end up with an experiment named abc,def

Issue Priority

Priority: 2 (default / most bugs should be filed as P2)

Issue Components

• Component: Python SDK
• Component: Java SDK
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• Component: IO connector
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• Component: Google Cloud Dataflow Runner

[Abacn]

To fix this one needs to implement a custom argparse action and set it here

beam/sdks/python/apache_beam/options/pipeline_options.py

Line 1415 in 9039608

action='append',

beam/sdks/python/apache_beam/options/pipeline_options.py

Line 980 in 9039608

action='append',