What is curl? How do I uninstall processing?

I installed processing on rapberry pi using the curl command.

curl https://processing.org/download/install-arm.sh | sudo sh

  1. How can I uninstall it?

Also, I try to compile some python programm but it gives some error:

from turtle import *

import * does not work in this environment.

processing.app.SketchException: import * does not work in this environment.
at jycessing.mode.run.SketchRunner.convertPythonSketchError(SketchRunner.java:242)
at jycessing.mode.run.SketchRunner.lambda$2(SketchRunner.java:119)
at java.lang.Thread.run(Thread.java:748)

  1. in upper right corner python mode is selected… why does it give a java error? And why does it give an error at all?