How can i randomly copy files and images from a directory to another?

My directory has hundreds of images and text files(.png and .txt). what's special about them is that each image has its own matching txt file, for example im1.png has img1.txt, news_im2.png has news_im2.png etc.. What i want is some way to give it a parameter or percentage, let's say 40 where it randomly copy 40% of the images along with their correspondent texts to a new file, and the most important word here is randomely as if i do the test again i shouldn't get the same results. Ideally i should be able to take 2 kind of parameters(reminder that the first would be the % of each sample) the second being number of samples for example maybe i want my data in 3 different samples randomly not only 2, in this case it should be able to take destination directories path equal to the number of samples i want and spread them accordingly, for example i shouldn't find img_1 in 2 different samples.

What i have done so far is simply set up my method to copy them because i couldn't find any random way to do my task in this example it would only copy images:

import glob, os, shutil


source_dir ='all_the_content/'
dest_dir = 'percentage_only/'
files = glob.iglob(os.path.join(source_dir, "*.png"))
for file in files:
     if os.path.isfile(file):
         shutil.copy2(file, dest_dir)