Update README

README.md

@@ -33,14 +33,15 @@ Outputs:
 
 ```py
 test.py:4 <module>:
-    whatever: [1, 2, 3] (list)
+    whatever: [1, 2, 3] (list) len=3
 ```
 
 
 That's only the tip of the iceberg, for example:
 
 ```py
 import numpy as np
+from devtools import debug
 
 data = {
     'foo': np.array(range(20)),
@@ -58,8 +59,8 @@ outputs:
 
 ## Usage without Import
 
-devtools can be used without `from devtools import debug` if you add `debug` into `__builtins__`
+devtools can be used without `from devtools import debug` if you add `debug` into `builtins`
 in `sitecustomize.py`.
 
-For instructions on adding `debug` to `__builtins__`,
+For instructions on adding `debug` to `builtins`,
 see the [installation docs](https://python-devtools.helpmanual.io/usage/#usage-without-import).