docs: def add_mutations_and_flush(self, table, muts):
          """
          Add mutations to a table without the need to create and manage a batch writer.
          """
          if not isinstance(muts, list) and not isinstance(muts, tuple):
              muts = [muts]
          cells = {}
          for mut in muts:
              cells.setdefault(mut.row, []).extend(mut.updates)
          self.client.updateAndFlush(self.login, table, cells)