'Deprecated alias for `clear_current()`.
.. versionchanged:: 5.0
Previously, this method would clear the `IOLoop` used as
the global singleton by `IOLoop.instance()`. Now that
`instance()` is an alias for `current()`,
`clear_instance()` is an alias for `clear_instance()`.
.. deprecated:: 5.0'

@staticmethod
def clear_instance():

    IOLoop.clear_current()
