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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 get_session_cookie(self):
 """ Create a session cookie object for use by aiohttp """


        if self._login is not None and self._password is not None:
            session_key = self.encode_user(self._login, self._password)
            return {'sessionkey': session_key}
        else:
            return None