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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def clear_search_defaults(self, args=None):
 """ Clear all search defaults specified by the list of parameter names given as ``args``. If ``args`` is not given, then clear all existing search defaults. Examples:: conn.set_search_defaults(scope=ldap.SCOPE_BASE, attrs=['cn']) conn.clear_search_defaults(['scope']) conn.clear_search_defaults() """

        if args is None:
            self._search_defaults.clear()
        else:
            for arg in args:
                if arg in self._search_defaults:
                    del self._search_defaults[arg]