code: def shell_config_for(shell, vexrc, environ):
      
      here = os.path.dirname(os.path.abspath(__file__))
      path = os.path.join(here, 'shell_configs', shell)
      try:
          with open(path, 'rb') as inp:
              data = inp.read()
      except FileNotFoundError as error:
          if error.errno != 2:
              raise
          return b''
      ve_base = vexrc.get_ve_base(environ).encode('ascii')
      if ve_base and not scary_path(ve_base) and os.path.exists(ve_base):
          data = data.replace(b'$WORKON_HOME', ve_base)
      return data
docs: return completion config for the named shell.