Andy Ye created BEAM-13968:
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Summary: Implement len(GroupBy) and ngroups for DataFrame API
Key: BEAM-13968
URL: https://issues.apache.org/jira/browse/BEAM-13968
Project: Beam
Issue Type: Sub-task
Components: dsl-dataframe, sdk-py-core
Reporter: Andy Ye
Assignee: Andy Ye-- This message was sent by Atlassian Jira (v8.20.1#820001)
