Manu Ganji Manu Ganji Case Insensitive Dict in Python Borrowing Kenneth Reitz code to implement case insensitive keys in Python Dict. It’s from the famous requests package. import collections class CaseInsensitiveDict(collections.MutableMapping): """A case-insensitive ``dict``-like object. Implements all methods and operations of ``collections.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. """ def __init__(self, data=None, **kwargs): self._store = collections.OrderedDict() if data is None: data = {} self.update(data, **kwargs) def __setitem__(self, key, value): # Use the lowercased key for lookups, but store the actual # key alongside the value. self._store[key.lower()] = (key, value) def __getitem__(self, key): return self._store[key.lower()][1] def __delitem__(self, key): del self._store[key.lower()] def __iter__(self): return (casedkey for casedkey, mappedvalue in self._store.values()) def __len__(self): return len(self._store) def lower_items(self): """Like iteritems(), but with all lowercase keys.""" return ( (lowerkey, keyval[1]) for (lowerkey, keyval) in self._store.items() ) def __eq__(self, other): if isinstance(other, collections.Mapping): other = CaseInsensitiveDict(other) else: return NotImplemented # Compare insensitively return dict(self.lower_items()) == dict(other.lower_items()) # Copy is required def copy(self): return CaseInsensitiveDict(self._store.values()) def __repr__(self): return str(dict(self.items())) Previous article Next article