Fix namedtuple issues that were uncovered by the 'self' changes

jedi/plugins/stdlib.py

@@ -84,7 +84,7 @@ class {typename}(tuple):
     # These methods were added by Jedi.
     # __new__ doesn't really work with Jedi. So adding this to nametuples seems
     # like the easiest way.
-    def __init__(_cls, {arg_list}):
+    def __init__(self, {arg_list}):
         'A helper function for namedtuple.'
         self.__iterable = ({arg_list})
 

test/test_inference/test_stdlib.py

@@ -60,8 +60,7 @@ def test_nested_namedtuples(Script):
         Dataset = collections.namedtuple('Dataset', ['data'])
         Datasets = collections.namedtuple('Datasets', ['train'])
         train_x = Datasets(train=Dataset('data_value'))
-        train_x.train.'''
-    ))
+        train_x.train.'''))
     assert 'data' in [c.name for c in s.complete()]