encode('hex') doesn't exist for bytes in python3

[Cypher1]

Might be able to make use of something similar to the following to get around this but I'm not sure about backwards compatability.

print ''.join('{:02x}'.format(x) for x in os.urandom(40))

From: https://stackoverflow.com/questions/19210414/byte-array-to-hex-string

[kalloc]

or use six

[russian-developer]

@Cypher1 can you make pull request please.

[Cypher1]

Do you have unit tests for this? If so I might be able to but haven't used this project in quite a while.