question: Who was the first US president to be formally impeached by Congress?
answerText: Andrew Johnson
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questionEntity.entityType: entity
questionEntity.label: President of the United States
questionEntity.mention: US president
questionEntity.name: Q11268
questionEntity.entityType: entity
questionEntity.label: United States Congress
questionEntity.mention: Congress
questionEntity.name: 1
questionEntity.entityType: ordinal
questionEntity.mention: first
answerEntity.name: Q8612
answerEntity.label: Andrew Johnson