docs: def keys(key, delimiter=DEFAULT_TARGET_DELIM):
      '''
      .. versionadded:: 2015.8.0
  
      Attempt to retrieve a list of keys from the named value from the pillar.
  
      The value can also represent a value in a nested dict using a ":" delimiter
      for the dict, similar to how pillar.get works.
  
      delimiter
          Specify an alternate delimiter to use when traversing a nested dict
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' pillar.keys web:sites
      '''
      ret = salt.utils.data.traverse_dict_and_list(
          __pillar__, key, KeyError, delimiter)
  
      if ret is KeyError:
          raise KeyError("Pillar key not found: {0}".format(key))
  
      if not isinstance(ret, dict):
          raise ValueError("Pillar value in key {0} is not a dict".format(key))
  
      return ret.keys()