code: def get_negation(event):
          
          states = event.get('states', [])
          if not states:
              return []
          negs = [state for state in states
                  if state.get('type') == 'NEGATION']
          neg_texts = [neg['text'] for neg in negs]
          return neg_texts
docs: Return negation attached to an event.
  
          Example: "states": [{"@type": "State", "type": "NEGATION",
                               "text": "n't"}]