another typo (#1675)

diff --git a/docs/advanced/classes.rst b/docs/advanced/classes.rst
index fe49459..99a95c7 100644
--- a/docs/advanced/classes.rst
+++ b/docs/advanced/classes.rst
@@ -153,7 +153,7 @@
 
 .. code-block:: python
 
-    class Dachschund(Dog):
+    class Dachshund(Dog):
         def __init__(self, name):
             Dog.__init__(self) # Without this, undefined behavior may occur if the C++ portions are referenced.
             self.name = name