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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_authenticated_connection(self, user, passwd, db='admin', ssl=True):
 """Get an authenticated connection to this instance. :param str user: The username to use for authentication. :param str passwd: The password to use for authentication. :param str db: The name of the database to authenticate against. Defaults to ``'Admin'``. :param bool ssl: Use SSL/TLS if available for this instance. Defaults to ``True``. :raises: :py:class:`pymongo.errors.OperationFailure` if authentication fails. """

        # Attempt to establish an authenticated connection.
        try:
            connection = self.get_connection(ssl=ssl)
            connection[db].authenticate(user, passwd)
            return connection

        # Catch exception here for logging, then just re-raise.
        except pymongo.errors.OperationFailure as ex:
            logger.exception(ex)
            raise