Check calls to all only if it's a name and not an attribute

src/_pytest/assertion/rewrite.py

@@ -964,7 +964,7 @@ warn_explicit(
         """
         visit `ast.Call` nodes on Python3.5 and after
         """
-        if call.func.id == "all":
+        if isinstance(call.func, ast.Name) and call.func.id == "all":
             return self.visit_all(call)
         new_func, func_expl = self.visit(call.func)
         arg_expls = []