```ruby
require 'spec_helper'

describe command('defaults read'), :if => os[:family] == 'darwin' do
  its(:exit_status) { should eq 0 }
end
```

Add test for `pip list` command
user
```ruby
require 'spec_helper'

describe command('defaults read'), :if => os[:family] == 'darwin' do
  its(:exit_status) { should eq 0 }
end

describe command('pip list') do
  its(:exit_status) { should eq 0 }
end
```
assistant