pattern_match is an abuse of some change to python syntax added in 3.8 with the walrus operator :=. It is code that has been carved out of Panoramix and not at all my original work.
kolinko built Tilde (here as pattern_match) which adds the ~ operator for pattern matching. A ~ denotes a pattern to be matched and then replaced with a series of := operators underneath. Because of this, Python 3.8 is required.
git clone https://github.com/caccavale/pattern_match
Currently, encodings are only available in imported modules so trying to run a file using pattern_match will fail:
$ python imports_pattern_match.py
File "imports_pattern_match.py", line 1
SyntaxError: encoding problem: pattern_match
To fix this, have an another file that imports the pattern_match using file:
$ cat wrapper.py
import imports_pattern_match
$ python wrapper.py