class_docstr: DEPRECATED since IPython 5.0
  
  Manage PyOS_InputHook for different GUI toolkits.
  
  This class installs various hooks under ``PyOSInputHook`` to handle
  GUI event loop integration.
class_docstr_tok: ["DEPRECATED","since","IPython","5.0","Manage","PyOS_InputHook","for","different","GUI","toolkits",".","This","class","installs","various","hooks","under","``","PyOSInputHook","``","to","handle","GUI","event","loop","integration","."]
docstr: DEPRECATED since IPython 5.0
  
  Clear IPython's internal reference to an application instance.
  
  Whenever we create an app for a user on qt4 or wx, we hold a
  reference to the app.  This is needed because in some cases bad things
  can happen if a user doesn't hold a reference themselves.  This
  method is provided to clear the references we are holding.
  
  Parameters
  ----------
  gui : None or str
      If None, clear all app references.  If ('wx', 'qt4') clear
      the app for that toolkit.  References are not held for gtk or tk
      as those toolkits don't have the notion of an app.
code: def clear_app_refs(self, gui=None):
      """DEPRECATED since IPython 5.0
  
      Clear IPython's internal reference to an application instance.
  
      Whenever we create an app for a user on qt4 or wx, we hold a
      reference to the app.  This is needed because in some cases bad things
      can happen if a user doesn't hold a reference themselves.  This
      method is provided to clear the references we are holding.
  
      Parameters
      ----------
      gui : None or str
          If None, clear all app references.  If ('wx', 'qt4') clear
          the app for that toolkit.  References are not held for gtk or tk
          as those toolkits don't have the notion of an app.
      """
      warn(
          "`clear_app_refs` is deprecated since IPython 5.0 and will be removed in future versions.",
          DeprecationWarning,
          stacklevel=2,
      )
      if gui is None:
          self.apps = {}
      elif gui in self.apps:
          del self.apps[gui]
  
imports: import os
  import platform
  import sys
  from distutils.version import LooseVersion
  from warnings import warn
label_desc: Use image node_id 7 for calling the InputHookManager obj's underlying member method code with example usage: obj.clear_app_refs(gui) without return types