CodeSkulptor is a Python implementation (in JavaScript) running in a browser. It implements a subset of Python 2.

CodeSkulptor3 is the same but it implements a subset of Python 3.

It is the environment used in the MOOC An Introduction to Interactive Programming in Python (Rice University, Coursera).

To use a program from CodeSkulptor in standard Python (with this package), you need to change import simplegui by import SimpleGUICS2Pygame.simpleguics2pygame as simplegui.

The right way to do is to write this

    import simplegui
except ImportError:
    import SimpleGUICS2Pygame.simpleguics2pygame as simplegui

and your program runs both in CodeSkulptor and standard Python.

So, if your program runs in CodeSkulptor, it imports simplegui. Else, an ImportError exception will be raised, and then it will imports SimpleGUICS2Pygame.simpleguics2pygame and it renamed to simplegui.

In this package a little script can help to quickly make this changement on program downloaded from CodeSkulptor.
Run python
The file is copied to before changing.

To use also the other modules, you can write this. But specify only those you use.

    import simplegui

    import codeskulptor
    import numeric
    import simpleplot

    import user305_SXBsmszNiUxIeoV as codeskulptor_lib
    import user305_SZNWcbqQHXN4pow as simplegui_lib
except ImportError:
    import SimpleGUICS2Pygame.simpleguics2pygame as simplegui

    import SimpleGUICS2Pygame.codeskulptor as codeskulptor
    import SimpleGUICS2Pygame.numeric as numeric
    import SimpleGUICS2Pygame.simpleplot as simpleplot

    import SimpleGUICS2Pygame.codeskulptor_lib as codeskulptor_lib
    import SimpleGUICS2Pygame.simplegui_lib as simplegui_lib

Note that import name like user305_SXBsmszNiUxIeoV in CodeSkulptor is valid both for CodeSkulptor 2 and CodeSkulptor3. It corresponds to URLs and .

Specific code

To run specific code on CodeSkulptor or with SimpleGUICS2Pygame, you can write this

    import simplegui

except ImportError:
    import SimpleGUICS2Pygame.simpleguics2pygame as simplegui


And then you can run specific code simply by testing value of SIMPLEGUICS2PYGAME. For example:

# …

def joypad_up(joypad, button):
    if joypad == 0:
        if button == 0:
            # …



SimpleGUICS2Pygame adds the possibility to use joypads. It is not available in CodeSkulptor. You can make compatible program with the previous tip to separate specific code.

Similarly to set_mouseclick_handler() and set_mousedrag_handler() functions, the class Frame in SimpleGUICS2Pygame defines _set_joypaddown_handler(), _set_joypadup_handler(), _set_joypadaxe_handler() and _set_joypadhat_handler().

Two little examples using joypads (but of course only when you run them with SimpleGUICS2Pygame directly on your computer): example/ and example/


The color parameter used by drawing functions must be in the following formats:

  • '#rrggbb' with rr, gg, bb hexadecimal numbers on 2 figures
  • '#rgb' with r, g, b hexadecimal numbers on 1 figure
  • 'rbg(red,blue,green)' with red, blue, green 0 <= integer <= 255
  • 'rgba(red,blue,green,alpha)' with red, blue, green 0 <= integer <= 255 and alpha between 0 and 1
  • a constant name in this list .

See the official HTML colors: .

Command line arguments

When you run a program you can use following arguments: python [SimpleGUICS2Pygame arguments] [application arguments]

  • --default-font: Use Pygame default font instead serif, monospace… (this is faster if you display a lot of text).
  • --display-fps: Display FPS average on the canvas.
  • --fps N: Set Frame Per Second (default: 60 FPS).
  • --frame-padding N: Set the padding in pixels found around the canvas (default: 2).
  • --fullscreen: Fullscreen mode.
  • --help: Print help message and quit.
  • --keep-timers: Keep running timers when close frame without asking (default: ask before close). See also --stop-timers.
  • --last: Mark this argument as the last SimpleGUICS2Pygame’s argument. (Do nothing else.)
  • --no-border: Window without border.
  • --no-controlpanel: Hide the control panel (and status boxes).
  • --no-load-sound: Don’t load any sound.
  • --no-status: Hide two status boxes.
  • --overwrite-downloaded-medias: Download all images and sounds from Web and save in local directory even if they already exist.
  • --print-application-args: Print remaining arguments transmit to application.
  • --print-args: Print final configuration from SimpleGUICS2Pygame’s argument.
  • --print-load-medias: Print URLs or local filenames loaded.
  • --print-stats-cache: After frame stopped, print some statistics of caches.
  • --save-downloaded-medias: Save images and sounds downloaded from Web that don’t already exist in local directory.
  • --stop-timers: Stop all timers when ending program (default: running timers continue, as in CodeSkulptor). See also --keep-timers.
  • --version: Print help message and quit.

If an argument is not in this list then it is ignored and all next arguments are ignored by SimpleGUICS2Pygame.

Arguments used by SimpleGUICS2Pygame is deleted to sys.argv. Remaining arguments can used by your application.

SimpleGUICS2Pygame arguments are automatically read when the module simpleguics2pygame is imported.

  • python --no-controlpanel --stop-timers --foo --fullscreen
    Run with the control panel hidden and timers will stoped. But SimpleGUICS2Pygame ignore --foo and --fullscreen. application receive --foo --fullscreen arguments.
  • python --no-controlpanel --last --stop-timers --foo --fps 30
    Run with the control panel hidden. But SimpleGUICS2Pygame ignore --stop-timers, --foo, --fps and 30. application receive --stop-timers --foo --fps 30 arguments.

Download medias

Run python --save-downloaded-medias --print-load-medias once. Images and sounds used (from URLs) will be saved in local directory (_img/ et _snd/ by default). Next simply run python and the medias will be loaded from these local directories.

For example, load_image('') save image to _img/

SimpleGUICS2Pygame has two additional classes to load directly local files: _LocalImage() and _LocalSound(). But be aware that these functions are not available in CodeSkulptor.

Helper functions

This package contains 5 additional modules with several helper functions that you can also import online in CodeSkulptor:

For example, to draw multiline text you can use draw_text_multi() from the simplegui_lib_draw module by:

    import simplegui

    import user305_SaT1YKoOikl4ax9 as simplegui_lib_draw
except ImportError:
    import SimpleGUICS2Pygame.simpleguics2pygame as simplegui

    import SimpleGUICS2Pygame.simplegui_lib as simplegui_lib_draw

def draw(canvas):
    # …
                    """line 1
line 2
line 3""", (x, y), size, 'white', 'serif')
    # …

Python assertions option

Run python then asserts is enabled and this package is (intentionnaly) very strict. So maybe “correct” programs in CodeSkulptor fail! (In fact CodeSkulptor is very permissive. Some incorrect Python codes are accepted.) It is a good point to develop and write correct programs. But if you want just run a program without annoying assertions you can disable them with. python -O

In some cases run without assertions is faster. See in the Comparison of speeds section, an example where SimpleGUICS2Pygame functions are executed a lot of times.

Ressources: images, sounds and example programs

Online images & sounds links

Python programs running in CodeSkulptor