Switch from black to ruff format

Ruff is faster and if it supports everything that black supports than why not? I
did have to pull in a more recent version from unstable, but that's easy to do
now. And I decided to just go ahead and configure ruff by turning on almost all
checks, which meant I had to fix a whole bunch of things, but I did that and
everything is okay now.

1 files changed, 16 insertions, 6 deletions

diff --git a/Biz/Bild/Example.py b/Biz/Bild/Example.py
index 5d165d8..1bd30ae 100644
--- a/Biz/Bild/Example.py
+++ b/Biz/Bild/Example.py
@@ -1,32 +1,42 @@
 """
+Test that bild can build Python stuff.
+
 Example Python file that also serves as a test case for bild.
 """
+
 # : out example
 # : dep cryptography
 import sys
+
 import cryptography.fernet
 
 
 def cryptic_hello(name: str) -> str:
-    "Example taken from `cryptography` docs."
+    """
+    Encrypt and decrypt `name`.
+
+    Example taken from `cryptography` docs.
+    """
     key = cryptography.fernet.Fernet.generate_key()
     f = cryptography.fernet.Fernet(key)
     token = f.encrypt(hello(name).encode("utf-8"))
     ret = f.decrypt(token).decode("utf-8")
-    assert ret == hello(name)
+    if ret != hello(name):
+        msg = "en/decryption failed!"
+        raise ValueError(msg)
     return ret
 
 
 def hello(name: str) -> str:
-    "Say hello"
+    """Say hello."""
     return f"Hello {name}"
 
 
 def main() -> None:
-    "Entrypoint"
+    """Entrypoint."""
     if "test" in sys.argv:
-        print("testing success")
-    print(cryptic_hello("world"))
+        sys.stdout.write("testing success")
+    sys.stdout.write(cryptic_hello("world"))
 
 
 if __name__ == "__main__":