Shortcut for add_route with method GET, if allow_head is true another
        route is added allowing head requests to the same endpoint

def add_get(self, path: str, handler: _WebHandler, *,
                name: Optional[str]=None, allow_head: bool=True,
                **kwargs: Any) -> AbstractRoute:
        """
        Shortcut for add_route with method GET, if allow_head is true another
        route is added allowing head requests to the same endpoint
        """
        resource = self.add_resource(path, name=name)
        if allow_head:
            resource.add_route(hdrs.METH_HEAD, handler, **kwargs)
        return resource.add_route(hdrs.METH_GET, handler, **kwargs)