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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 set_acl(self, acl, mode):
 """Sets the ACL of this file. in acl of type str The ACL specification string. To-be-defined. in mode of type int UNIX-style mode mask to use if @a acl is empty. As mention in :py:func:`IGuestSession.directory_create` this is realized on a best effort basis and the exact behavior depends on the Guest OS. raises :class:`OleErrorNotimpl` The method is not implemented yet. """

        if not isinstance(acl, basestring):
            raise TypeError("acl can only be an instance of type basestring")
        if not isinstance(mode, baseinteger):
            raise TypeError("mode can only be an instance of type baseinteger")
        self._call("setACL",
                     in_p=[acl, mode])