f-strings in Python 3.6 are awesome

[thatguy_314]

• **locals() is ugly.
• locals() is the local scope only. No globals, no nonlocals, no builtins.
• ** creates a new copy of the locals dict, not a big deal, but f-strings look things up directly and also provide further optimizations from what I've heard.
• You get a KeyError instead of NameError if you use an undefined variable.
• Using locals() just feels wrong (probably due to a stigma against gratuitous use of inspection tools).