defmain():

second_step(file_path)

deffirst_step(url,file_path,username,password):

download_file.download_with_auth(url,file_path,username,password)

defsecond_step(file_path):

im=Image.open(file_path)

green_data=im.getdata(green_channel)

datas=list(green_data)

datas_len=len(datas)

foriinrange(int(datas_len/2)):

left=datas[index]

right=datas[index+1]

abs_left_min_right=abs(left-right)

ifabs_left_min_right!=42:

message+=chr(abs_left_min_right)

print(message)

if__name__=="__main__":

main()

Solve Problems inhttp://www.pythonchallenge.com

result:http://www.pythonchallenge.com/pc/ring/guido.html

- use image.split() to split RGB channels

- im.bands() return number of im's channels

- ring means "green" if you visit "green.html" will get response "yes"

- whodunnit is an word means "who is the murderer"

result:http://www.pythonchallenge.com/pc/ring/bell.html auth=(repeat, switch)

- author use python2 keyword, but there is some different with python3