Need help with this, using the pycrypto library in python 2.7: This homework is

Question

Need help with this, using the pycrypto library in python 2.7:

This homework is designed to practice with hash functions.The files for this homework is at http://www.cs.fsu.edu/~zzhang/CIS4360_Fall_2016_files/HW2files.zip

In this problem, you are asked to implement a very simple hash function, in any language you like, which takes an input array of bytes of any length and turns it into a 4-byte hash. It calculates the hash as follows:

If the input length measured in the number of bytes is not a multiple of 4, add 0s to the end until it is a multiple of 4.

Divide the input array into 4-byte blocks.

Calculate the exclusive-or of all blocks as the hash output.

Please use the hash function to find the hash of file “HW2P1input”, and submit it as the answer to this problem

Sample output:

Problem 1: if the file is "abcdefghij", the output should be 6d6e0e0c. Note that the file has 8 characters but the length is 11, because the last one is ' ' and is hidden.

Explanation / Answer

These old hashes defined my requirements:

Without further ado, here's the fastest hash I've been able to design that meets all the requirements. The comments describe how to use it.

Update: I'm leaving the old hash in the text below, but it's obsolete, I have faster and more thorough hashes now. http://burtleburtle.net/bob/c/lookup3.c (2006) is about 2 cycles/byte, works well on 32-bit platforms, and can produce a 32 or 64 bit hash. SpookyHash (2011) is specific to 64-bit platforms, is about 1/3 cycle per byte, and produces a 32, 64, or 128 bit hash.

Most hashes can be modeled like this:

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