code: def upload(self, sys_id, file_path, name=None, multipart=False):
          
  
          if not isinstance(multipart, bool):
              raise InvalidUsage('Multipart must be of type bool')
  
          resource = self.resource
  
          if name is None:
              name = os.path.basename(file_path)
  
          resource.parameters.add_custom({
              'table_name': self.table_name,
              'table_sys_id': sys_id,
              'file_name': name
          })
  
          data = open(file_path, 'rb').read()
          headers = {}
  
          if multipart:
              headers["Content-Type"] = "multipart/form-data"
              path_append = '/upload'
          else:
              headers["Content-Type"] = "text/plain"
              path_append = '/file'
  
          return resource.request(method='POST', data=data, headers=headers, path_append=path_append)
docs: Attaches a new file to the provided record
  
          :param sys_id: the sys_id of the record to attach the file to
          :param file_path: local absolute path of the file to upload
          :param name: custom name for the uploaded file (instead of basename)
          :param multipart: whether or not to use multipart
          :return: the inserted record