Update cheatsheets

tldr/python-m-json.tool

@@ -0,0 +1,18 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# python -m json.tool
+
+> Validate and pretty-print JSON data.
+> Part of Python's standard library.
+> More information: <https://docs.python.org/library/json.html#module-json.tool>.
+
+- Pretty-print JSON from a file:
+
+`python -m json.tool {{path/to/file.json}}`
+
+- Validate and pretty-print JSON from standard input:
+
+`echo '{{{"key": "value"}}}' | python -m json.tool`