Sublime key binding for converting to tabs

gistfile1.txt

// requires the chain of command sublime plugin
// https://github.com/jisaacks/ChainOfCommand
[
	{
		"keys": ["shift+alt+a"],
		"command": "chain",
		"args": {
			"commands": [
				["set_setting", {"setting": "tab_size", "value": 2}],
				["unexpand_tabs", {"set_translate_tabs" : true}],
				["set_setting", {"setting": "tab_size", "value": 4}]
			]
		}
	}
]