class_docstr: A class for managing multiple kernels.
class_docstr_tok: ["A","class","for","managing","multiple","kernels","."]
docstr: check that a kernel id is valid
code: def _check_kernel_id(self, kernel_id):
      """check that a kernel id is valid"""
      if kernel_id not in self:
          raise KeyError("Kernel with id not found: %s" % kernel_id)
  
imports: from __future__ import absolute_import
  import os
  import uuid
  import zmq
  from traitlets.config.configurable import LoggingConfigurable
  from ipython_genutils.importstring import import_item
  from traitlets import Any, Bool, Dict, DottedObjectName, Instance, Unicode, default, observe
  from ipython_genutils.py3compat import unicode_type
  from .kernelspec import NATIVE_KERNEL_NAME, KernelSpecManager
label_desc: Use image node_id 20 for calling the MultiKernelManager obj's underlying member method code with example usage: obj._check_kernel_id(kernel_id) without return types