question how to download snapchat contents with only the username link

hi does anyone here know how to download snapchat contents of a person how do people rip snapchat girls contents is there any software to download snapchat contents. i have a few/models girls snapchat usernames and i would like to know how to download snapchat contents. is there anyway like copy a person snapchat username into like a software and it downloads all the contents of that username
if anyone knows how to do that then please share the method.