prevent itf to be an unbound variable in _cominterface_meta.__get_baseinterface_methodcount

[junkmd]

Since itf can be an unbound variable, the following code will cause several type checkers to warn.

comtypes/comtypes/_post_coinit/unknwn.py

Lines 325 to 336 in 97cbe1c

	def __get_baseinterface_methodcount(self):
	"Return the number of com methods in the base interfaces"
	try:
	result = 0
	for itf in self.mro()[1:-1]:
	result += len(itf.__dict__["_methods_"])
	return result
	except KeyError as err:
	(name,) = err.args
	if name == "_methods_":
	raise TypeError("baseinterface '%s' has no _methods_" % itf.__name__)
	raise

But this try...except... clause traps a KeyError.

Therefore, it is possible to change to a better code by verifying the existence of the key.

-        try:
-            result = 0
-            for itf in self.mro()[1:-1]:
+        result = 0
+        for itf in self.mro()[1:-1]:
+            if "_methods_" in itf.__dict__:
                 result += len(itf.__dict__["_methods_"])
-            return result
-        except KeyError as err:
-            (name,) = err.args
-            if name == "_methods_":
-                raise TypeError("baseinterface '%s' has no _methods_" % itf.__name__)
-            raise
+            else:
+                raise TypeError(f"baseinterface '{itf.__name__}' has no _methods_")
+        return result

Maybe vars(itf) is better than itf.__dict__, or maybe there is another way to write it better, but I'll leave it to the contributors for fixing this.