docs: def to_list(i, use_keys=False):
      '''
      Converts items to a list.
  
      :param i: Item to convert
  
          * If `i` is ``None``, the result is an empty list
  
          * If `i` is 'string', the result won't be \
          ``['s', 't', 'r',...]`` rather more like ``['string']``
  
          * If `i` is a nested dictionary, the result will be a flattened list.
  
      :param use_keys:
          If i is a dictionary, use the keys instead of values
      :returns:
          All items in i as list
      '''
  
      from photon.util.system import shell_notify
  
      if not i:
          return []
      if isinstance(i, str):
          return [i]
      if isinstance(i, list):
          return i
      if isinstance(i, dict):
          res = list()
          for e in i.keys() if use_keys else i.values():
              res.append(to_list(e)) if isinstance(e, dict) else res.append(e)
          return res
      shell_notify('type for %s uncovered' % (i), state=True, more=type(i))