Support visitors with class and static methods

Also, add missing type definitions in printer module.

Author: Cito

.mypy.ini

@@ -7,9 +7,6 @@ warn_redundant_casts = True
 warn_unused_ignores = True
 disallow_untyped_defs = True
 
-[mypy-graphql.language.printer]
-disallow_untyped_defs = False
-
 [mypy-graphql.pyutils.frozen_dict]
 disallow_untyped_defs = False
 

README.md

@@ -14,7 +14,7 @@ a query language for APIs created by Facebook.
 
 The current version 3.1.1 of GraphQL-core is up-to-date with GraphQL.js version 15.0.0.
 
-An extensive test suite with over 2100 unit tests and 100% coverage comprises a
+An extensive test suite with over 2200 unit tests and 100% coverage comprises a
 replication of the complete test suite of GraphQL.js, making sure this port is
 reliable and compatible with GraphQL.js.