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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 server_info(self, session=None):
 """Get information about the MongoDB server we're connected to. :Parameters: - `session` (optional):
 a :class:`~pymongo.client_session.ClientSession`. .. versionchanged:: 3.6 Added ``session`` parameter. """

        return self.admin.command("buildinfo",
                                  read_preference=ReadPreference.PRIMARY,
                                  session=session)