python interpreter isn't running on any of my notebooks

I am trying to use python on my notebooks. I have both java and python added to my Environment Variables, and I have the library py4j installed, too. Also I have added the local host that I am using to the Zeppelin-site.xml file 

I am simply typing:

%python

print ("hi") 

but it keeps showing the following error every time I run it for any of my notebooks: 

java.lang.OutOfMemoryError: Java heap space at org.apache.thrift.protocol.TBinaryProtocol.readStringBody(TBinaryProtocol.java:379) at org.apache.thrift.protocol.TBinaryProtocol.readMessageBegin(TBinaryProtocol.java:230) at org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:69) at org.apache.zeppelin.interpreter.thrift.RemoteInterpreterService$Client.recv_createInterpreter(RemoteInterpreterService.java:209) at org.apache.zeppelin.interpreter.thrift.RemoteInterpreterService$Client.createInterpreter(RemoteInterpreterService.java:192) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter$2.call(RemoteInterpreter.java:169) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter$2.call(RemoteInterpreter.java:165) at org.apache.zeppelin.interpreter.remote.RemoteInterpreterProcess.callRemoteFunction(RemoteInterpreterProcess.java:135) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter.internal_create(RemoteInterpreter.java:165) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter.open(RemoteInterpreter.java:132) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter.getFormType(RemoteInterpreter.java:299) at org.apache.zeppelin.notebook.Paragraph.jobRun(Paragraph.java:407) at org.apache.zeppelin.scheduler.Job.run(Job.java:188) at org.apache.zeppelin.scheduler.RemoteScheduler$JobRunner.run(RemoteScheduler.java:307) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)