code: def item_str_path(keys, dct):
      
      return item_path(map(lambda segment: int(segment) if isint(segment) else segment, keys.split('.')), dct)
docs: Given a string of path segments separated by ., splits them into an array. Int strings are converted
          to numbers to serve as an array index
      :param keys: e.g. 'foo.bar.1.goo'
      :param dct: e.g. dict(foo=dict(bar=[dict(goo='a'), dict(goo='b')])
      :return: The resolved value or an error. E.g. for above the result would be b