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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_many(self, block, update_dict):
 """ Update many fields on an XBlock simultaneously. :param block: the block to update :type block: :class:`~xblock.core.XBlock` :param update_dict: A map of field names to their new values :type update_dict: dict """

        for key, value in six.iteritems(update_dict):
            self.set(block, key, value)