seti6.py

train_dir = os.path.join('./data/train')
data_signal_files = glob.glob(train_dir+'/*/*.png')
sample_files = [data_signal_files[idx] for idx in range(0, 5600, 800+10)]
sample_files

# Output
['./data/train/brightpixel/272_brightpixel.png',
 './data/train/squigglesquarepulsednarrowband/6438_squigglesquarepulsednarrowband.png',
 './data/train/narrowbanddrd/2012_narrowbanddrd.png',
 './data/train/squarepulsednarrowband/1396_squarepulsednarrowband.png',
 './data/train/narrowband/5923_narrowband.png',
 './data/train/noise/4753_noise.png',
 './data/train/squiggle/5826_squiggle.png']