Simplify json load/dump usage

Author: evanrrees

docs/cheatsheet/json-yaml.md

@@ -12,7 +12,7 @@ JSON stands for JavaScript Object Notation and is a lightweight format for stori
 ```python
 >>> import json
 >>> with open("filename.json", "r") as f:
-...     content = json.loads(f.read())
+...     content = json.load(f)
 ```
 
 Write a JSON file with:
@@ -22,7 +22,7 @@ Write a JSON file with:
 
 >>> content = {"name": "Joe", "age": 20}
 >>> with open("filename.json", "w") as f:
-...     f.write(json.dumps(content, indent=2))
+...     json.dump(content, f, indent=2)
 ```
 
 ## YAML