old_contents: 
  class Skill(object):
  
      classes = [
          (["집앞", "버스"], "bus_stop"),
          (["초지역", "버스"], "bus_stop"),
          (["주간", "작업 리포트"], "toggl_report"),
          (["주간", "커밋"], "github_commit"),
          (["미세먼지"], "air_quality"),
          (["toggl Feedly"], "toggl_timer"),
          (["toggl Inbox Zero"], "toggl_timer"),
          (["toggl Book"], "toggl_timer"),
          (["toggl Pocket"], "toggl_timer"),
          (["toggl Morning Paper"], "toggl_timer")
      ]
  
new_contents: 
  class Skill(object):
  
      classes = [
          (["집앞", "버스"], "bus_stop"),
          (["초지역", "버스"], "bus_stop"),
          (["주간", "작업 리포트"], "toggl_report"),
          (["주간", "커밋"], "github_commit"),
          (["미세먼지"], "air_quality")
      ]
  
subject: remove classes using toggl