Spelling and grammar fixes in code comments and documentation
diff --git a/Python/ast.c b/Python/ast.c
index e5d7ac6..2b7aed8 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -2179,7 +2179,7 @@
        testlist: test (',' test)* [',']
        augassign: '+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^='
                 | '<<=' | '>>=' | '**=' | '//='
-       test: ... here starts the operator precendence dance
+       test: ... here starts the operator precedence dance
      */
 
     if (NCH(n) == 1) {