Clean Code: Apply flake8-simplify to Python

Also flake8-comprehensions which was added to the CI

For flake8-simplify, there are a few false-positives,
e.g. https://github.com/MartinThoma/flake8-simplify/issues/115

26_Chomp/python/chomp.py

@@ -18,9 +18,7 @@ class Canvas:
 
     def render(self):
         lines = ["       1 2 3 4 5 6 7 8 9"]
-        row = 0
-        for line in self._buffer:
-            row += 1
+        for row, line in enumerate(self._buffer, start=1):
             lines.append(" " + str(row) + " " * 5 + " ".join(line))
         return "\n".join(lines)