text: """Definition for base executor."""
  
  import abc
  from typing import TypeVar
  
  ExecutorT = TypeVar("ExecutorT", bound="BaseExecutor")
  
  
  class BaseExecutor(abc.ABC):
      """Base executor for queries."""
  
      @abc.abstractmethod
      def as_json(self: ExecutorT) -> ExecutorT:  # pragma: no cover
          """Create an executor copy that will use JSON as output format.
  
          Returns:
              Copied executor.
          """
  