在pyspark中，可以用另一列填充In吗？

from pyspark.sql import SparkSession
from pyspark.sql.functions import col

# 创建SparkSession
spark = SparkSession.builder.getOrCreate()

# 创建示例数据集
data = [("Alice", 25, "F", None),
        ("Bob", 30, "M", "Engineer"),
        ("Charlie", None, "M", "Doctor")]

df = spark.createDataFrame(data, ["name", "age", "gender", "profession"])

# 使用另一列填充空值
filled_df = df.fillna({"age": df.select(col("age")).na.drop().first()[0]})

filled_df.show()