class_docstr: A generic container for immutable data that can be accessed either by
  numeric index or by key. This is similar to an
  :class:`collections.OrderedDict` except that the keys are optional and
  iteration over it returns the values instead of keys.
  
  This is the base class for both :class:`.Column` and :class:`.Row`.
  
  :param values:
      A sequence of values.
  :param keys:
      A sequence of keys.
docstr: Set values by index, which we want to fail loudly.
docstr_tok: ["Set","values","by","index",",","which","we","want","to","fail","loudly","."]
code: def __setitem__(self, key, value):
      """
      Set values by index, which we want to fail loudly.
      """
      raise TypeError(
          "Rows and columns can not be modified directly. You probably need to compute a new column."
      )
  
imports: from collections import OrderedDict
  from collections.abc import Sequence
  from agate.utils import memoize
label_desc: Use image node_id 8 for calling the MappedSequence obj's underlying member method code with example usage: obj.__setitem__(key, value) without return types