Imports github.com/apache/beam/sdks/go/pkg/beam github.com/apache/beam/sdks/go/pkg/beam/runners/dataflow github.com/apache/beam/sdks/go/pkg/beam/runners/direct github.com/apache/beam/sdks/go/pkg/beam/runners/flink github.com/apache/beam/sdks/go/pkg/beam/runners/spark Standard library imports context flag os testing