```ruby
module Twat::Subcommands
  class Finger < Base

    def run
      raise ArgumentRequired if @argv.length == 0
      auth!

      begin
        Twitter.user_timeline(@argv[0], :count => @argv[1] || 1).each do |tweet|
          format(tweet)
        end
      rescue Twitter::NotFound
        puts "#{@argv[0].bold.red} doesn't appear to be a valid user"
      end
    end

    def self.usage
      "Usage: twat finger USERNAME [count]"
    end

  end
  COMMANDS['finger'] = Finger
end
```

Update to use internal spec
user
```ruby
module Twat::Subcommands
  class Finger < Base

    def run
      needs_arguments(1)
      auth!

      begin
        Twitter.user_timeline(@argv[0], :count => @argv[1] || 1).each do |tweet|
          format(tweet)
        end
      rescue Twitter::NotFound
        puts "#{@argv[0].bold.red} doesn't appear to be a valid user"
      end
    end

    def self.usage
      "Usage: twat finger USERNAME [count]"
    end

  end
  COMMANDS['finger'] = Finger
end
```
assistant