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https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/datastream/operators/windows/#tumbling-windows
https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/datastream/operators/windows/#sliding-windows
https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/datastream/operators/windows/#session-windows
https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/datastream/operators/windows/#global-windows