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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_runner(classpath, main, jvm_options, args, executor, cwd, distribution, create_synthetic_jar, synthetic_jar_dir):
 """Gets the java runner for execute_java and execute_java_async."""


  executor = executor or SubprocessExecutor(distribution)

  safe_cp = classpath
  if create_synthetic_jar:
    safe_cp = safe_classpath(classpath, synthetic_jar_dir)
    logger.debug('Bundling classpath {} into {}'.format(':'.join(classpath), safe_cp))

  return executor.runner(safe_cp, main, args=args, jvm_options=jvm_options, cwd=cwd)