如何从Scala的迭代列表中创建DataFrame？

import org.apache.spark.sql.{SparkSession, Row}
import org.apache.spark.sql.types.{StructType, StructField, StringType, IntegerType}

val spark = SparkSession.builder()
  .appName("Creating DataFrame from Iteration List")
  .master("local")
  .getOrCreate()

val schema = StructType(
  Seq(
    StructField("name", StringType, nullable = true),
    StructField("age", IntegerType, nullable = true)
  )
)

val rdd = spark.sparkContext.emptyRDD[Row]

val list = List(("John", 30), ("Lisa", 25), ("Mike", 35))
val rows = list.map(item => Row(item._1, item._2))
val newRdd = rdd.union(spark.sparkContext.parallelize(rows))

val df = spark.createDataFrame(newRdd, schema)