```ruby
class Visit < Cask
  url 'http://portal.nersc.gov/svn/visit/trunk/releases/2.6.3/VisIt-2.6.3-x86_64-installer.dmg'
  homepage 'https://wci.llnl.gov/codes/visit/home.html'
  version '2.6.3'
  sha1 '3091da14bdad48e4f0faa0f543743d5befde11f2'
  link 'VisIt.app'
end
```

Update VisIt cask version to 2.7.0.
user
```ruby
class Visit < Cask
  url 'http://portal.nersc.gov/svn/visit/trunk/releases/2.7.0/VisIt-2.7.0-x86_64-installer.dmg'
  homepage 'https://wci.llnl.gov/codes/visit/home.html'
  version '2.7.0'
  sha1 'be44ee53695553396895154e7c9916bb670f772c'
  link 'VisIt.app'
end
```
assistant