spark.pyspark.driver.python when set in code doesnt work

spark.pyspark.driver.python, spark.pyspark.python when set in code doesnt get picked up by driver or executor. It gets picked up only when set through --conf or when set in spark-defaults.conf. Can we add a line which states it is illegal to set these in application as we do for spark.driver.extraJavaOptions in the doc https://spark.apache.org/docs/latest/configuration.html#application-properties