https://beam.apache.org/releases/javadoc/2.23.0/org/apache/beam/sdk/schemas/transforms/CoGroup.ExpandCrossProduct.html
CoGroup.ExpandCrossProduct (Apache Beam 2.23.0)
apache beam
https://beam.apache.org/releases/javadoc/2.39.0/org/apache/beam/sdk/schemas/transforms/CoGroup.ExpandCrossProduct.html
CoGroup.ExpandCrossProduct (Apache Beam 2.39.0)
apache beam