=============== Data Structures

.. module:: werkzeug.datastructures

Werkzeug provides some subclasses of common Python objects to extend them with additional features. Some of them are used to make them immutable, others are used to change some semantics to better work with HTTP.

General Purpose

.. versionchanged:: 0.6 The general purpose classes are now pickleable in each protocol as long as the contained objects are pickleable. This means that the :class:FileMultiDict won't be pickleable as soon as it contains a file.

.. autoclass:: TypeConversionDict :members:

.. autoclass:: ImmutableTypeConversionDict :members: copy

.. autoclass:: MultiDict :members: :inherited-members:

.. class:: OrderedMultiDict

Works like a regular :class:`MultiDict` but preserves the
order of the fields.  To convert the ordered multi dict into a
list you can use the :meth:`items` method and pass it ``multi=True``.

In general an :class:`OrderedMultiDict` is an order of magnitude
slower than a :class:`MultiDict`.

.. admonition:: note

   Due to a limitation in Python you cannot convert an ordered
   multi dict into a regular dict by using ``dict(multidict)``.
   Instead you have to use the :meth:`to_dict` method, otherwise
   the internal bucket objects are exposed.

.. deprecated:: 3.1
    Will be removed in Werkzeug 3.2. Use ``MultiDict`` instead.

.. class:: ImmutableOrderedMultiDict

An immutable :class:`OrderedMultiDict`.

.. deprecated:: 3.1
    Will be removed in Werkzeug 3.2. Use ``ImmutableMultiDict`` instead.

.. versionadded:: 0.6

.. autoclass:: CombinedMultiDict

.. autoclass:: ImmutableDict :members: copy

.. autoclass:: ImmutableList

.. autoclass:: FileMultiDict :members:

.. _http-datastructures:

HTTP Related

.. autoclass:: Headers([defaults]) :members:

.. autoclass:: EnvironHeaders

.. autoclass:: HeaderSet :members:

.. autoclass:: Accept :members:

.. autoclass:: MIMEAccept :members: accept_html, accept_xhtml, accept_json

.. autoclass:: CharsetAccept

.. autoclass:: LanguageAccept

.. autoclass:: RequestCacheControl :members: :inherited-members: ImmutableDictMixin, CallbackDict :member-order: groupwise

.. autoclass:: ResponseCacheControl :members: :inherited-members: CallbackDict :member-order: groupwise

.. autoclass:: ETags :members:

.. autoclass:: Authorization :members:

.. autoclass:: WWWAuthenticate :members:

.. autoclass:: IfRange :members:

.. autoclass:: Range :members:

.. autoclass:: ContentRange :members:

Others

.. autoclass:: FileStorage :members:

.. attribute:: stream

  The input stream for the uploaded file.  This usually points to an
  open temporary file.

.. attribute:: filename

  The filename of the file on the client. Can be a ``str``, or an
  instance of ``os.PathLike``.

.. attribute:: name

  The name of the form field.

.. attribute:: headers

  The multipart headers as :class:`Headers` object.  This usually contains
  irrelevant information but in combination with custom multipart requests
  the raw headers might be interesting.

  .. versionadded:: 0.6