Method register

awscli/botocore/session.py:665–705

Register a handler with an event. :type event_name: str :param event_name: The name of the event. :type handler: callable :param handler: The callback to invoke when the event is emitted. This object must be callable, and must accept ``**kwa

(
        self, event_name, handler, unique_id=None, unique_id_uses_count=False
    )

        log.addHandler(ch)

    def register(
        self, event_name, handler, unique_id=None, unique_id_uses_count=False
    ):
        """Register a handler with an event.

        :type event_name: str
        :param event_name: The name of the event.

        :type handler: callable
        :param handler: The callback to invoke when the event
            is emitted.  This object must be callable, and must
            accept ``**kwargs``.  If either of these preconditions are
            not met, a ``ValueError`` will be raised.

        :type unique_id: str
        :param unique_id: An optional identifier to associate with the
            registration.  A unique_id can only be used once for
            the entire session registration (unless it is unregistered).
            This can be used to prevent an event handler from being
            registered twice.

        :param unique_id_uses_count: boolean
        :param unique_id_uses_count: Specifies if the event should maintain
            a count when a ``unique_id`` is registered and unregisted. The
            event can only be completely unregistered once every register call
            using the unique id has been matched by an ``unregister`` call.
            If ``unique_id`` is specified, subsequent ``register``
            calls must use the same value for  ``unique_id_uses_count``
            as the ``register`` call that first registered the event.

        :raises ValueError: If the call to ``register`` uses ``unique_id``
            but the value for ``unique_id_uses_count`` differs from the
            ``unique_id_uses_count`` value declared by the very first
            ``register`` call for that ``unique_id``.
        """
        self._events.register(
            event_name,
            handler,
            unique_id,
            unique_id_uses_count=unique_id_uses_count,
        )

    def unregister(
        self,