title: Spark only working with python 2
body: <p>Beginner to Spark here.</p>
  
  <pre><code>uname -a
  </code></pre>
  
  <p>Linux debian 3.2.0-4-amd64 #1 SMP Debian 3.2.82-1 x86_64 GNU/Linux</p>
  
  <p>I've downloaded the default Spark at <a href="http://spark.apache.org/downloads.html" rel="nofollow noreferrer">http://spark.apache.org/downloads.html</a></p>
  
  <p>I want to use it with Python3.
  I've added followings lines to my <code>.bashrc</code>:</p>
  
  <pre><code>export SPRK_HOME=/home/rictus/spark-2.0.2-bin-hadoop2.7
  export PATH=$SPARK_HOME/bin:$PATH
  export PYSPARK_PYTHON=python3
  </code></pre>
  
  <p>And just to test, I've launched python examples at 
      /home/rictus/spark-2.0.2-bin-hadoop2.7/examples/src/main/python
  using following command lines </p>
  
  <pre><code>. /home/rictus/.bashrc
  cd /home/rictus/spark-2.0.2-bin-hadoop2.7/examples/src/main/python
  spark-submit pi.py
  </code></pre>
  
  <p>Spark launch and stop with a <code>stacktrace</code> coming from python :</p>
  
  <pre>
  rictus:~/spark-2.0.2-bin-hadoop2.7/examples/src/main/python$ spark-submit pi.py 
  16/11/22 22:51:49 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
  16/11/22 22:51:50 WARN Utils: Your hostname, debian resolves to a loopback address: 127.0.1.1; using 10.0.2.15 instead (on interface eth0)
  16/11/22 22:51:50 WARN Utils: Set SPARK_LOCAL_IP if you need to bind to another address
  [Stage 0:>                                                          (0 + 0) / 2]16/11/22 22:51:53 ERROR Executor: Exception in task 0.0 in stage 0.0 (TID 0)
  org.apache.spark.api.python.PythonException: Traceback (most recent call last):
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/worker.py", line 143, in main
      importlib.invalidate_caches()
  AttributeError: 'module' object has no attribute 'invalidate_caches'
  
      at org.apache.spark.api.python.PythonRunner$$anon$1.read(PythonRDD.scala:193)
      at org.apache.spark.api.python.PythonRunner$$anon$1.(PythonRDD.scala:234)
      at org.apache.spark.api.python.PythonRunner.compute(PythonRDD.scala:152)
      at org.apache.spark.api.python.PythonRDD.compute(PythonRDD.scala:63)
      at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:319)
      at org.apache.spark.rdd.RDD.iterator(RDD.scala:283)
      at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:70)
      at org.apache.spark.scheduler.Task.run(Task.scala:86)
      at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:745)
  16/11/22 22:51:53 WARN TaskSetManager: Lost task 0.0 in stage 0.0 (TID 0, localhost): org.apache.spark.api.python.PythonException: Traceback (most recent call last):
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/worker.py", line 143, in main
      importlib.invalidate_caches()
  AttributeError: 'module' object has no attribute 'invalidate_caches'
  
      at org.apache.spark.api.python.PythonRunner$$anon$1.read(PythonRDD.scala:193)
      at org.apache.spark.api.python.PythonRunner$$anon$1.(PythonRDD.scala:234)
      at org.apache.spark.api.python.PythonRunner.compute(PythonRDD.scala:152)
      at org.apache.spark.api.python.PythonRDD.compute(PythonRDD.scala:63)
      at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:319)
      at org.apache.spark.rdd.RDD.iterator(RDD.scala:283)
      at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:70)
      at org.apache.spark.scheduler.Task.run(Task.scala:86)
      at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:745)
  
  16/11/22 22:51:53 ERROR TaskSetManager: Task 0 in stage 0.0 failed 1 times; aborting job
  [Stage 0:>                                                          (0 + 1) / 2]16/11/22 22:51:53 WARN TaskSetManager: Lost task 1.0 in stage 0.0 (TID 1, localhost): TaskKilled (killed intentionally)
  Traceback (most recent call last):
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/examples/src/main/python/pi.py", line 43, in 
      count = spark.sparkContext.parallelize(range(1, n + 1), partitions).map(f).reduce(add)
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/rdd.py", line 802, in reduce
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/rdd.py", line 776, in collect
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/py4j-0.10.3-src.zip/py4j/java_gateway.py", line 1133, in __call__
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/sql/utils.py", line 63, in deco
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/py4j-0.10.3-src.zip/py4j/protocol.py", line 319, in get_return_value
  py4j.protocol.Py4JJavaError: An error occurred while calling z:org.apache.spark.api.python.PythonRDD.collectAndServe.
  : org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 0.0 failed 1 times, most recent failure: Lost task 0.0 in stage 0.0 (TID 0, localhost): org.apache.spark.api.python.PythonException: Traceback (most recent call last):
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/worker.py", line 143, in main
      importlib.invalidate_caches()
  AttributeError: 'module' object has no attribute 'invalidate_caches'
  
      at org.apache.spark.api.python.PythonRunner$$anon$1.read(PythonRDD.scala:193)
      at org.apache.spark.api.python.PythonRunner$$anon$1.(PythonRDD.scala:234)
      at org.apache.spark.api.python.PythonRunner.compute(PythonRDD.scala:152)
      at org.apache.spark.api.python.PythonRDD.compute(PythonRDD.scala:63)
      at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:319)
      at org.apache.spark.rdd.RDD.iterator(RDD.scala:283)
      at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:70)
      at org.apache.spark.scheduler.Task.run(Task.scala:86)
      at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:745)
  
  Driver stacktrace:
      at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1454)
      at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1442)
      at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1441)
      at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
      at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
      at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1441)
      at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:811)
      at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:811)
      at scala.Option.foreach(Option.scala:257)
      at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:811)
      at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:1667)
      at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1622)
      at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1611)
      at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:48)
      at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:632)
      at org.apache.spark.SparkContext.runJob(SparkContext.scala:1873)
      at org.apache.spark.SparkContext.runJob(SparkContext.scala:1886)
      at org.apache.spark.SparkContext.runJob(SparkContext.scala:1899)
      at org.apache.spark.SparkContext.runJob(SparkContext.scala:1913)
      at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:912)
      at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
      at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
      at org.apache.spark.rdd.RDD.withScope(RDD.scala:358)
      at org.apache.spark.rdd.RDD.collect(RDD.scala:911)
      at org.apache.spark.api.python.PythonRDD$.collectAndServe(PythonRDD.scala:453)
      at org.apache.spark.api.python.PythonRDD.collectAndServe(PythonRDD.scala)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:606)
      at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:237)
      at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
      at py4j.Gateway.invoke(Gateway.java:280)
      at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
      at py4j.commands.CallCommand.execute(CallCommand.java:79)
      at py4j.GatewayConnection.run(GatewayConnection.java:214)
      at java.lang.Thread.run(Thread.java:745)
  Caused by: org.apache.spark.api.python.PythonException: Traceback (most recent call last):
    File "/home/rictus/spark-2.0.2-bin-hadoop2.7/python/lib/pyspark.zip/pyspark/worker.py", line 143, in main
      importlib.invalidate_caches()
  AttributeError: 'module' object has no attribute 'invalidate_caches'
  
      at org.apache.spark.api.python.PythonRunner$$anon$1.read(PythonRDD.scala:193)
      at org.apache.spark.api.python.PythonRunner$$anon$1.(PythonRDD.scala:234)
      at org.apache.spark.api.python.PythonRunner.compute(PythonRDD.scala:152)
      at org.apache.spark.api.python.PythonRDD.compute(PythonRDD.scala:63)
      at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:319)
      at org.apache.spark.rdd.RDD.iterator(RDD.scala:283)
      at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:70)
      at org.apache.spark.scheduler.Task.run(Task.scala:86)
      at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:274)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      ... 1 more
  </pre>
  
  <p>I'm confused. The file <code>pi.py</code> seems to not be Python2-specific.</p>
  
  <p>I don't know what to do with this part of the <code>stacktrace</code>:</p>
  
  <blockquote>
    <p>AttributeError: 'module' object has no attribute 'invalidate_caches'</p>
  </blockquote>
  
  <p>In my <code>.bashrc</code> file, if I change <code>PYSPARK_PYTHON</code> from <code>python3</code> to <code>python2</code>, everything is working fine.</p>
  
  <p>Is my Spark compile to only work with Python2? It seems silly to me. Is there something I'm missing?</p>