对于pyspark中给定的id，如何在无界前移和忽略当前行日期值之间获取最大值？

from pyspark.sql import SparkSession
from pyspark.sql.window import Window
from pyspark.sql.functions import col, lag, when

spark = SparkSession.builder.getOrCreate()

df = spark.createDataFrame([(1, '2022-01-01'), (1, '2022-01-02'), (1, '2022-01-03'), 
                            (2, '2022-01-01'), (2, '2022-01-02'), (2, '2022-01-03')], 
                           ['id', 'date'])

df = df.orderBy('id', col('date').desc())

window_spec = Window.partitionBy('id').orderBy(col('date').desc())

df = df.withColumn('max_date', when(lag(col('date')).over(window_spec) < col('date'), col('date')).otherwise(lag(col('date')).over(window_spec)))

df.show()