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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 user_is_submission_owner(self, submission):
 """ Returns true if the current user is the owner of this jobid, false else """

        if not self._user_manager.session_logged_in():
            raise Exception("A user must be logged in to verify if he owns a jobid")

        return self._user_manager.session_username() in submission["username"]