The Python SDK library does not support fallback assets in product_bundle key like the API does.
Following the steps described here:
with 'analytic_sr_udm2,analytic_udm2' string will lead to the following error:
planet.specs.SpecificationException: bundle - 'analytic_sr_udm2,analytic_udm2' is not one of 'analytic_udm2', 'analytic_3b_udm2', 'analytic_8b_udm2', 'visual', 'basic_analytic_udm2', 'basic_analytic_8b_udm2', 'analytic_sr_udm2', 'analytic_8b_sr_udm2'.


