 Complete the following phrase:  In addition to developing the AMG F1 W09 EQ Power chassis, Mercedes unveiled plans to completely redesign their power unit for the 2018 championship to ensure continuous development until the next generation of engine scheduled for début in 2021. The engine was the subject of attention for an engine mode nicknamed party mode, which delivered a performance boost over one lap and was used by the team in qualifying. The first specification was introduced at the opening round of the 2018 Formula One World Championship season and was used for 7 consecutive races, from Australia to 