address reviews

Author: mgaido91

sql/core/src/main/scala/org/apache/spark/sql/UDFRegistration.scala

@@ -58,6 +58,7 @@ class UDFRegistration private[sql] (functionRegistry: FunctionRegistry) extends
         | pythonIncludes: ${udf.func.pythonIncludes}
         | pythonExec: ${udf.func.pythonExec}
         | dataType: ${udf.dataType}
+        | udfDeterministic: ${udf.udfDeterministic}
       """.stripMargin)
 
     functionRegistry.createOrReplaceTempFunction(name, udf.builder)

sql/core/src/main/scala/org/apache/spark/sql/execution/python/PythonUDF.scala

@@ -30,10 +30,10 @@ case class PythonUDF(
     dataType: DataType,
     children: Seq[Expression],
     evalType: Int,
-    udfDeterministic: Boolean = true)
+    udfDeterministic: Boolean)
   extends Expression with Unevaluable with NonSQLExpression with UserDefinedExpression {
 
-  override lazy val deterministic = udfDeterministic && children.forall(_.deterministic)
+  override lazy val deterministic: Boolean = udfDeterministic && children.forall(_.deterministic)
 
   override def toString: String = s"$name(${children.mkString(", ")})"