tests: Format all Python code with black, except tests in basics subdir.

This adds the Python files in the tests/ directory to be formatted with
./tools/codeformat.py.  The basics/ subdirectory is excluded for now so we
aren't changing too much at once.

In a few places `# fmt: off`/`# fmt: on` was used where the code had
special formatting for readability or where the test was actually testing
the specific formatting.

tests/float/string_format_fp30.py

@@ -1,11 +1,12 @@
 def test(fmt, *args):
-    print('{:8s}'.format(fmt) + '>' +  fmt.format(*args) + '<')
+    print("{:8s}".format(fmt) + ">" + fmt.format(*args) + "<")
+
 
 test("{:10.4}", 123.456)
 test("{:10.4e}", 123.456)
 test("{:10.4e}", -123.456)
-#test("{:10.4f}", 123.456)
-#test("{:10.4f}", -123.456)
+# test("{:10.4f}", 123.456)
+# test("{:10.4f}", -123.456)
 test("{:10.4g}", 123.456)
 test("{:10.4g}", -123.456)
 test("{:10.4n}", 123.456)
@@ -15,8 +16,8 @@ test("{:g}", 300)
 
 test("{:10.4E}", 123.456)
 test("{:10.4E}", -123.456)
-#test("{:10.4F}", 123.456)
-#test("{:10.4F}", -123.456)
+# test("{:10.4F}", 123.456)
+# test("{:10.4F}", -123.456)
 test("{:10.4G}", 123.456)
 test("{:10.4G}", -123.456)
 
@@ -25,17 +26,17 @@ test("{:06e}", float("-inf"))
 test("{:06e}", float("nan"))
 
 # The following fails right now
-#test("{:10.1}", 0.0)
+# test("{:10.1}", 0.0)
 
 print("%.0f" % (1.750000 % 0.08333333333))
 # Below isn't compatible with single-precision float
-#print("%.1f" % (1.750000 % 0.08333333333))
-#print("%.2f" % (1.750000 % 0.08333333333))
-#print("%.12f" % (1.750000 % 0.08333333333))
+# print("%.1f" % (1.750000 % 0.08333333333))
+# print("%.2f" % (1.750000 % 0.08333333333))
+# print("%.12f" % (1.750000 % 0.08333333333))
 
 # tests for errors in format string
 
 try:
-    '{:10.1b}'.format(0.0)
+    "{:10.1b}".format(0.0)
 except ValueError:
-    print('ValueError')
+    print("ValueError")