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| -rw-r--r-- | Doc/library/collections.rst | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst index 5298dbcabe..71c27ed848 100644 --- a/Doc/library/collections.rst +++ b/Doc/library/collections.rst @@ -41,6 +41,8 @@ Python's general purpose built-in containers, :class:`dict`, :class:`list`, :class:`ChainMap` objects ------------------------- +.. versionadded:: 3.3 + A :class:`ChainMap` class is provided for quickly linking a number of mappings so they can be treated as a single unit. It is often much faster than creating a new dictionary and running multiple :meth:`~dict.update` calls. @@ -91,8 +93,6 @@ The class can be used to simulate nested scopes and is useful in templating. The use-cases also parallel those for the builtin :func:`super` function. A reference to ``d.parents`` is equivalent to: ``ChainMap(*d.maps[1:])``. - .. versionadded:: 3.3 - Example of simulating Python's internal lookup chain:: import builtins |