Translating to python3

[TheodoreEhrenborg]

• [x] Cython compatibility
• [x] print is a function
• [x] integer division does not work
• [x] range() now means python2's xrange()
• [x] raw_input becomes input
• [x] exceptions might be raised/execepted differently

[TheodoreEhrenborg]

Unfortunately pickle is not able to read the saved weights of the neural networks.