I've just created a cool service for presenting charts in Flask. Here's a test deployment hosted on my laptop. If you find any issue, just send me a link - I'll check if everything is fine. Flag is in
/flag.https://web-art.ecsc18.hack.cert.pl
Update 2018-06-25 21:15: Unfortunately my laptop is very slow and my browser hangs on websites with long addresses, so I asked my friend to create an extension for me that limits the url to 1024 characters. Now it works smoothly!
Format flagi:
ecsc{litery_cyfry_i_znaki_specjalne}.