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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 getManager(self, force=False):
 """Extract the YadisServiceManager for this object's URL and suffix from the session. @param force: True if the manager should be returned regardless of whether it's a manager for self.url. @return: The current YadisServiceManager, if it's for this URL, or else None """

        manager = self.session.get(self.getSessionKey())
        if (manager is not None and (manager.forURL(self.url) or force)):
            return manager
        else:
            return None