code: def cmd_usercheck(username, no_cache, verbose, wopen):
      
  
      habucfg = loadcfg()
  
      if verbose:
          logging.basicConfig(level=logging.INFO, format='%(message)s')
  
      if not no_cache:
          homedir = pwd.getpwuid(os.getuid()).pw_dir
          requests_cache.install_cache(homedir + '/.habu_requests_cache')
          logging.info('using cache on ' + homedir + '/.habu_requests_cache')
  
      existent = {}
  
      for site, url in urls.items():
          u = url.format(username)
          logging.info(u)
          try:
              r = requests.head(u, allow_redirects=False)
          except Exception:
              continue
          if r.status_code == 200:
              if requests.head(url.format('zei4fee3q9'), allow_redirects=False).status_code == 200:
                  logging.error('Received status 200 for user zei4fee3q9, maybe, the check needs to be fixed')
              else:
                  existent[site] = u
                  if wopen:
                      webbrowser.open_new_tab(u)
  
      print(json.dumps(existent, indent=4))
docs: Check if the given username exists on various social networks and other popular sites.
  
      \b
      $ habu.usercheck portantier
      {
          "aboutme": "https://about.me/portantier",
          "disqus": "https://disqus.com/by/portantier/",
          "github": "https://github.com/portantier/",
          "ifttt": "https://ifttt.com/p/portantier",
          "lastfm": "https://www.last.fm/user/portantier",
          "medium": "https://medium.com/@portantier",
          "pastebin": "https://pastebin.com/u/portantier",
          "pinterest": "https://in.pinterest.com/portantier/",
          "twitter": "https://twitter.com/portantier",
          "vimeo": "https://vimeo.com/portantier"
      }