code: def merge(self, from_email, source_incidents):
          
          if from_email is None or not isinstance(from_email, six.string_types):
              raise MissingFromEmail(from_email)
  
          add_headers = {'from': from_email, }
          endpoint = '/'.join((self.endpoint, self.id, 'merge'))
          incident_ids = [entity['id'] if isinstance(entity, Entity) else entity
                          for entity in source_incidents]
          incident_references = [{'type': 'incident_reference', 'id': id_}
                                 for id_ in incident_ids]
  
          return self.__class__.create(
              endpoint=endpoint,
              api_key=self.api_key,
              add_headers=add_headers,
              data_key='source_incidents',
              data=incident_references,
              method='PUT',
          )
docs: Merge other incidents into this incident.