You don't need the UUID
{B4BFCC3A-DB2C-424C-B029-7FE99A87C641}
because the constants are defined in the library.
from win32comext.shell import shell
documents = shell.SHGetKnownFolderPath(shell.FOLDERID_Documents)
downloads = shell.SHGetKnownFolderPath(shell.FOLDERID_Downloads)