Built In Python Hash() Function
Answer : As stated in the documentation, built-in hash() function is not designed for storing resulting hashes somewhere externally. It is used to provide object's hash value, to store them in dictionaries and so on. It's also implementation-specific (GAE uses a modified version of Python). Check out: >>> class Foo: ... pass ... >>> a = Foo() >>> b = Foo() >>> hash(a), hash(b) (-1210747828, -1210747892) As you can see, they are different, as hash() uses object's __hash__ method instead of 'normal' hashing algorithms, such as SHA. Given the above, the rational choice is to use the hashlib module. Use hashlib as hash() was designed to be used to: quickly compare dictionary keys during a dictionary lookup and therefore does not guarantee that it will be the same across Python implementations. The response is absolutely no surprise: in fact In [1]: -5768830964305142685L & 0xffffffff Out[1]: 1934711907L...