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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 signed_session(self, session=None):
 """Create token-friendly Requests session, using auto-refresh. Used internally when a request is made. If a session object is provided, configure it directly. Otherwise, create a new session and return it. :param session: The session to configure for authentication :type session: requests.Session """

        self.set_token() # Adal does the caching.
        self._parse_token()
        return super(AADMixin, self).signed_session(session)