Some of the other differences between Python versions 2 and 3 are …
print is a command in version 2, and a function in version 3. So in version 3, the values to be output must be enclosed in parentheses.
To prompt for and collect user input, with version 2 you should use the
raw_input function, while in version 3, you need to use the
/ division operator performs floating point division in version 3, while in version 2, the type of division depends upon the types of the operands.
If you attempt to do the MMOOC with version 3, you may, at first, find that it is easy to adapt the code between the two Python versions, but as the course proceeds, adaptation will become increasingly complex. For the three projects in the final weeks of the course, it would take a huge amount of work to adapt them to version 3, because they use existing code modules that are written for version 2. So, imo, it seems advisable to do the entire MMOOC in version 2. I have IDLE 2 and 3 on the same machine, and it has caused no problem.