Question: where did the phrase keep calm and carry on originate
[{'answer': 'the British government in 1939', 'provenance': [{'wikipedia_id': '21875788', 'title': 'Keep Calm and Carry On', 'start_paragraph_id': 1, 'start_character': 60, 'end_paragraph_id': 1, 'end_character': 90, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '21875788', 'title': 'Keep Calm and Carry On', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 620, 'bleu_score': 0.925800253895223, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16271971983508409277}, 'section': 'Section::::Abstract.'}]}]