Spelling and grammar fixes in code comments and documentation
diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py
index 7ebc236..3d46220 100755
--- a/Parser/asdl_c.py
+++ b/Parser/asdl_c.py
@@ -136,7 +136,7 @@
 
 
 class StructVisitor(EmitVisitor):
-    """Visitor to generate typdefs for AST."""
+    """Visitor to generate typedefs for AST."""
 
     def visitModule(self, mod):
         for dfn in mod.dfns: