Correct typo in the help text
@@ -18,7 +18,7 @@ var (
// to an existing type or may describe a completely new type using a list of
// attributes (object fields). Attribute types may themselves be user type.
// When a user type is defined as an alias to another type it may define
-// additional validations - for example it a user type which is an alias of
+// additional validations - for example if a user type which is an alias of
// String may define a validation pattern that all instances of the type
// must match.
//
