code: def __init__(
      self, jvm: JVMView, jbackend: JavaObject, jhc: JavaObject
  ):
      super(Py4JBackend, self).__init__()
      import base64
  
      def decode_bytearray(encoded):
          return base64.standard_b64decode(encoded)
  
      # By default, py4j's version of this function does extra
      # work to support python 2. This eliminates that.
      py4j.protocol.decode_bytearray = decode_bytearray
  
      self._jvm = jvm
      self._hail_package = getattr(self._jvm, "is").hail
      self._utils_package_object = scala_package_object(
          self._hail_package.utils
      )
      self._jbackend = jbackend
      self._jhc = jhc
  
      self._backend_server = (
          self._hail_package.backend.BackendServer.apply(self._jbackend)
      )
      self._backend_server_port: int = self._backend_server.port()
      self._backend_server.start()
      self._requests_session = requests.Session()
  
      self._registered_ir_function_names: Set[str] = set()
  
      # This has to go after creating the SparkSession. Unclear why.
      # Maybe it does its own patch?
      install_exception_handler()
      from hail.context import version
  
      py_version = version()
      jar_version = self._jhc.version()
      if jar_version != py_version:
          raise RuntimeError(
              f"Hail version mismatch between JAR and Python library\n"
              f"  JAR:    {jar_version}\n"
              f"  Python: {py_version}"
          )
  
imports: from typing import Mapping, Set, Tuple
  import abc
  import socket
  import socketserver
  import sys
  from threading import Thread
  import orjson
  import requests
  import py4j
  from py4j.java_gateway import JavaObject, JVMView
  import hail
  from hail.expr import construct_expr
  from hail.ir import JavaIR
  from hail.utils.java import FatalError, Env, scala_package_object
  from .backend import ActionTag, Backend, fatal_error_from_java_error_triplet
  from ..hail_logging import Logger
  import http.client
label_desc: Use image node_id 1 to create a new Py4JBackend object from inherited base classes: Backend with example: obj = Py4JBackend(jvm, jbackend, jhc)