requests.structures.CaseInsensitiveDict

A case-insensitive ``dict``-like object. Implements all methods and operations of ``MutableMapping`` as well as dict's ``copy``. Also provides ``lower_items``. All keys are expected to be strings. The structure remembers the case of the last key to be set, and ``iter(instance)``, ``keys()``, ``items()``, ``iterkeys()``, and ``iteritems()`` will contain case-sensitive keys. However, querying and contains testing is case insensitive:: cid = CaseInsensitiveDict() cid['Accept'] = 'application/json' cid['aCCEPT'] == 'application/json' # True list(cid) == ['Accept'] # True For example, ``headers['content-encoding']`` will return the value of a ``'Content-Encoding'`` response header, regardless of how the header name was originally stored. If the constructor, ``.update``, or equality comparison operations are given keys that have equal ``.lower()``s, the behavior is undefined.