In his 2017 PyCon Israel keynote, "The Fun of Reinvention", Dave Beazley made a wonderfully mischievous case for taking advantage of new Python features instead

In his 2017 PyCon Israel keynote, "The Fun of Reinvention", Dave Beazley made a wonderfully mischievous case for taking advantage of new Python features instead of making every new project carry the accumulated baggage of old Python versions. Talking about Python 3.6, he said it was "probably one of the most major Python releases that has ever been made." His demonstration intentionally used new features that made the code incompatible with older interpreters. This was a prototype, so why not use the interesting new tools? He was especially enthusiastic about f-strings: "F-strings are just awesome." I was originally skeptical about them, but he convinced me to reconsider. One implementation detail that later helped win me over was that CPython 3.6 added dedicated FORMAT_VALUE and BUILD_STRING opcodes for f-strings. That does not mean an f-string is faster than simply doing a + b when both values are already strings -- simple concatenation usually wins that particular race -- but f-strings are generally cleaner, and often faster than older formatting machinery such as str.format(). I agree with his argument. There are vanishingly few situations in which a new project genuinely must support ancient Python releases. If your employer refuses to let you use a reasonably current version without a concrete technical reason, that is a warning sign. Life is too short to program indefinitely for obsolete interpreters. The keynote: https://www.youtube.com/watch?v=js_0wjzuMfc https://www.youtube.com/watch?v=js_0wjzuMfc Beazley's other talks: https://www.dabeaz.com/talks.html https://www.dabeaz.com/talks.html