Fully implementing Bitcoin white paper would require moderate amount of work if you do not consider every little detail related to security of your client code.

Fully implementing Bitcoin white paper would require moderate amount of work if you do not consider every little detail related to security of your client code. However, current Bitcoin protocol added many features such as scripting. I think one can maintain code readability in a python implementation but documentation is the key here. Developer needs to clearly state the objective of each function. For ethereum, you need one external element called: Ethereum Virtual Machine. Smart Contracts are basically byte code that runs on EVM. Without it, blockchain cannot function. So, ethereum development may require extra knowledge on top of blockchain technology.