[docs] [issue37145] collections.abc.MappingView mixins rely on undocumented _mapping

Geoffrey Sneddon <geoffers+pythonbugs@gmail.com> added the comment: You've missed my point: the arguments that MappingView.__init__ takes are undocumented. Nowhere mentions class MappingView(mapping), as I would expect from how initializers are documented elsewhere. ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue37145> _______________________________________