Update pep-3155.txt (#183)

pep-3155.txt

@@ -62,7 +62,7 @@ Proposal
 This PEP proposes the addition of a ``__qualname__`` attribute to
 functions and classes.  For top-level functions and classes, the
 ``__qualname__`` attribute is equal to the ``__name__`` attribute.  For
-nested classed, methods, and nested functions, the ``__qualname__``
+nested classes, methods, and nested functions, the ``__qualname__``
 attribute contains a dotted path leading to the object from the module
 top-level.  A function's local namespace is represented in that dotted
 path by a component named ``<locals>``.