Python: add test for sub class

Author: yoff

python/ql/test/library-tests/frameworks/flask/flask_subclass.py

@@ -0,0 +1,14 @@
+from flask import Flask
+
+
+class Sub(Flask):
+    def __init__(self, *args, **kwargs):
+        Flask.__init__(self, *args, **kwargs)
+
+
+app = Sub(__name__) # $ MISSING: instance
+
+
+@app.route("/")
+def hello():
+    return "world"