Alter the hash function of a dictionary

Question

Following this question, we know that two different dictionaries, dict_1 and dict_2 for example, use the exact same hash function.

Is there any way to alter the hash function used by the dictionary?_{Negative answers also accepted!}

Answer 1

You can't change the hash-function - the dict will call hash on the keys it's supposed to insert, and that's that.

However, you can wrap the keys to provide different __hash__ and __eq__-Methods.

class MyHash(object):
     def __init__(self, v):
         self._v = v

     def __hash__(self):
         return hash(self._v) * -1

     def __eq__(self, other):
         return self._v == other._v

If this actually helps anything with your original problem/question I doubt though, it seems rather a custom array/list-based data-structure might be the answer. Or not.