```ruby
class SketchBeta < Cask
  version '3.1'
  sha256 'b567fe5ed071822d8917573d52e93acdc921dc924b77eee9ede2a41e88ce03ba'

  url 'https://rink.hockeyapp.net/api/2/apps/0172d48cceec171249a8d850fb16276b/app_versions/37?format=zip&avtoken=985ff642ddb110cfeb7998ffbc5993ef80bbfcf7'
  homepage 'http://bohemiancoding.com/sketch/beta/'
  license :unknown

  app 'Sketch Beta.app'
end
```

Upgrade Sketch Beta to v3.1.1
user
```ruby
class SketchBeta < Cask
  version '3.1.1'
  sha256 '4d4785f3356079f224bd64302ab17e651ba00752e364f08f146e67196a0a0fbc'

  url 'https://rink.hockeyapp.net/api/2/apps/0172d48cceec171249a8d850fb16276b/app_versions/49?format=zip&avtoken=2ab011a5b37200a2947be20cb2dd21af7af9265c'
  homepage 'http://bohemiancoding.com/sketch/beta/'
  license :unknown

  app 'Sketch Beta.app'
end
```
assistant