code: def send_video(self, recipient_id, video_path, notification_type=NotificationType.regular):
          
          return self.send_attachment(recipient_id, "video", video_path, notification_type)
docs: Send video to the specified recipient.
          Video should be MP4 or MOV, but supports more (https://www.facebook.com/help/218673814818907).
          https://developers.facebook.com/docs/messenger-platform/send-api-reference/video-attachment
          Input:
              recipient_id: recipient id to send to
              video_path: path to video to be sent
          Output:
              Response from API as <dict>