human
Solve the following python programming problem given the following code:
@ util.deprecated ('0.7', 'See :class:`.DDLEvents`, as well as :meth:`.DDLElement.execute_if`.') 
def execute_at(self, event_name, target) : 
    "Link execution of this DDL to the DDL lifecycle of a SchemaItem.

        Links this ``DDLElement`` to a ``Table`` or ``MetaData`` instance,
        executing it when that schema item is created or dropped. The DDL
        statement will be executed using the same Connection and transactional
        context as the Table create/drop itself. The ``.bind`` property of
        this statement is ignored.

        :param event:
          One of the events defined in the schema item's ``.ddl_events``;
          e.g. 'before-create', 'after-create', 'before-drop' or 'after-drop'

        :param target:
          The Table or MetaData instance for which this DDLElement will
          be associated with.

        A DDLElement instance can be linked to any number of schema items.

        ``execute_at`` builds on the ``append_ddl_listener`` interface of
        :class:`.MetaData` and :class:`.Table` objects.

        Caveat: Creating or dropping a Table in isolation will also trigger
        any DDL set to ``execute_at`` that Table's MetaData.  This may change
        in a future release.

        " 
    def call_event(target, connection, **kw) : 
        if self._should_execute_deprecated (event_name, target, connection, ** kw) : 
            return connection.execute (self.against (target)) 
event.listen (target, ('' + event_name.replace ('-', '_')), target) 

    
    

    Fix the buggy line: event.listen (target, ('' + event_name.replace ('-', '_')), target)
assistant
#Here is Python code to fix the buggy line: event.

event.listen (target, ('' + event_name.replace ('-', '_')), def call_event()