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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 start_session(self, causal_consistency=True, default_transaction_options=None):
 """Start a logical session. This method takes the same parameters as :class:`~pymongo.client_session.SessionOptions`. See the :mod:`~pymongo.client_session` module for details and examples. Requires MongoDB 3.6. It is an error to call :meth:`start_session` if this client has been authenticated to multiple databases using the deprecated method :meth:`~pymongo.database.Database.authenticate`. A :class:`~pymongo.client_session.ClientSession` may only be used with the MongoClient that started it. :Returns: An instance of :class:`~pymongo.client_session.ClientSession`. .. versionadded:: 3.6 """

        return self.__start_session(
            False,
            causal_consistency=causal_consistency,
            default_transaction_options=default_transaction_options)