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Stimuli won't draw

Hi all! I have written a brief script to test my computer’s timing with a photo diode, all in the hopes of adapting my study for EEG. I’m coming across a peculiar error wherein the stimuli that I am drawing do not appear, no matter how I try forcing them to with stimuli.draw(). This script has worked before, yet I accidentally must have reverted to an older version of it and now the stimuli (a series of circles borrowed from my ‘real’ stimulus presentation script) will not pop up. No error messages occur, and the script runs seemingly fine besides this issue.

The stimuli are 12 circles arranged in a circle. Example circle:

    noon = visual.Circle(

        win=win, name='12',

        size=(0.60, 0.60),

        ori=0, pos=(0, vis_deg),

        lineWidth=7, lineColor=None, lineColorSpace='rgb',

        fillColor=None, fillColorSpace='rgb',

        opacity=1, depth=0.0, interpolate=True)


The main body of code, designed to flash circles on screen and send triggers to our serial port:

for n in range(n_trials):
    for stim in stimuli:

    for n in range(30):

    for stim in stimuli:

    for n in range(30):

Thank you in advance!

Seconds after posting this I’ve realized my silly error-- I wasn’t giving the circles any color! Nevermind.