How dict objects are pickled?
pickle, python
Solution
The pickle module handles a number of types "natively". The types it doesn't handle natively will need to implement the "pickle protocol". Dicts, and simple subclasses, are handled natively.
Problem
After reading pickle documentation, I got an impression that a class needs to implement either `__reduce__` or `__getstate__` to get pickled correctly. But how pickling of dictionaries work then? They don't have any of those attributes: ``` > dict(a=1).__reduce__() --------------------------------------------------------------------------- TypeError Traceback (most recent call last) /home/daniyar/work/Apr24/<ipython-input-30-bc1cbd43305b> in <module>() ----> 1 dict(a=1).__reduce__() /usr/lib/python2.6/copy_reg.pyc in _reduce_ex(self, proto) 68 else: 69 if base is self.__class__: ---> 70 raise TypeError, "can't pickle %s objects" % base.__name__ 71 state = base(self) 72 args = (self.__class__, base, state) TypeError: can't pickle dict objects > dict(a=1).__getstate__() --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) /home/daniyar/work/Apr24/<ipython-input-31-00932fb40067> in <module>() ----> 1 dict(a=1).__getstate__() AttributeError: 'dict' object has no attribute '__getstate__' ``` Also, how classes derived from dict are pickled?