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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 ReadUsers(self, database_link, options=None):
 """Reads all users in a database. :params str database_link: The link to the database. :params dict options: The request options for the request. :return: Query iterable of Users. :rtype: query_iterable.QueryIterable """

        if options is None:
            options = {}

        return self.QueryUsers(database_link, None, options)