--- a/python/tkSnack.py	2024-04-20 16:01:28.403396211 +0200
+++ b/python/tkSnack.py	2024-04-20 16:01:55.094084757 +0200
@@ -267,7 +267,7 @@
         
     def pitch(self, method=None, **kw):
         """Returns a list of pitch values."""
-        if method is None or method is "amdf" or method is "AMDF":
+        if method is None or method == "amdf" or method == "AMDF":
             result = self.tk.call((self.name, 'pitch') + self._options(kw))
             return self._getdoubles(result)
         else: