如何将Spark DataFrame中的嵌套结构转换为嵌套映射

from pyspark.sql.functions import to_json, from_json
from pyspark.sql.types import StringType, MapType

from pyspark.sql.types import StructType, StructField, StringType, IntegerType

# 定义嵌套结构的模式
nested_schema = StructType([
    StructField("field1", StringType(), True),
    StructField("field2", IntegerType(), True),
    # 添加其他字段...
])

# 将嵌套结构列转换为JSON字符串
df_with_json = df.withColumn("nested_json", to_json(df.nested_col))

# 将JSON字符串列转换为嵌套映射
df_with_map = df_with_json.withColumn("nested_map", from_json(df_with_json.nested_json, nested_schema))