code: def update(args):
      
      if args.SITE:
          site = find_site(args.SITE, path=args.path)
          return site.run_update()
  
      for site in gen_sites(args.path):
          site.run_update()
      return True
docs: Run site update
      ---------------
  
      Run updates for site or all installed.
  
      ::
  
          usage: main.py update [-h] [-v] [-p PATH] [SITE]
  
          Run site update
  
          positional arguments:
          SITE                  Path to site or name (project.branch)
  
          optional arguments:
          -p PATH, --path PATH  path to makesite sites instalation dir. you can set it
                                  in $makesite_home env variable.
  
      Examples: ::
  
          # Update all makesite instances on server
          $ makesite update
  
          # Update by project name
          makesite update intaxi
  
          # Update by project name
          makesite update intaxi.develop
  
          # Update by project path
          makesite update /var/www/intaxi/master