Avoided closing the database connection within a transaction.

        """

        Helper routine for calling PostGIS functions and returning their result.

        """

        cursor = self.connection._cursor()

        try:

            try:

                cursor.execute('SELECT %s()' % func)

                row = cursor.fetchone()

            except:

                # Responsibility of callers to perform error handling.

                raise

        finally:

        # Close out the connection.  See #9437.

            self.connection.close()

        return row[0]

        with self.connection.temporary_connection() as cursor:

            cursor.execute('SELECT %s()' % func)

            return cursor.fetchone()[0]

    def postgis_geos_version(self):

        "Returns the version of the GEOS library used with PostGIS."

        Context manager that ensures that a connection is established, and

        if it opened one, closes it to avoid leaving a dangling connection.

        This is useful for operations outside of the request-response cycle.

        Provides a cursor: with self.temporary_connection() as cursor: ...

        """

        must_close = self.connection is None

        cursor = self.cursor()

        try:

            yield

            yield cursor

        finally:

            cursor.close()

            if must_close: