fart.py

# I've tried both of these:
try:
  for part in parts:
    dirs = [dir for dir in os.listdir(path_to_check) if not isfile(os.path.join(path_to_check, dir))]
    
    if "thing" in dirs:
      return path_to_check
    del path_parts[-1]
  else: 
    raise ValueError("thing not found")
except ValueError as e:
  print(e.value())
#############################  
for part in parts:
  dirs = [dir for dir in os.listdir(path_to_check) if not isfile(os.path.join(path_to_check, dir))]
    
  if "thing" in dirs:
    return path_to_check
  del path_parts[-1]
else: 
  raise ValueError("thing not found")
 
# test
with self.assertRaises(ValueError):
  self.stupid_function()