1. vscode中按“ctrl+shift+p”调出搜索栏，在搜索栏中输入snippet，点击“代码片段：配置用户代码片段”
   
2. 点击后，会显示如下列表，我们要设置是的Python,因此需要点击python.json，（第一次设置时python.json的位置在下拉列表按字母排序“p"的位置，设置过一次后，python.json会跑到下拉列表上方。）
   
3. 打开python.json文件后, 会有如下代码显示

{
	// Place your snippets for python here. Each snippet is defined under a snippet name and has a prefix, body and 
	// description. The prefix is what is used to trigger the snippet and the body will be expanded and inserted. Possible variables are:
	// $1, $2 for tab stops, $0 for the final cursor position, and ${1:label}, ${2:another} for placeholders. Placeholders with the 
	// same ids are connected.
	// Example:
	// "Print to console": {
	// 	"prefix": "log",
	// 	"body": [
	// 		"console.log('$1');",
	// 		"$2"
	// 	],
	// 	"description": "Log output to console"
	// }
}

复制其中的

	// "Print to console": {
	// 	"prefix": "log",
	// 	"body": [
	// 		"console.log('$1');",
	// 		"$2"
	// 	],
	// 	"description": "Log output to console"
	// }

用ctrl+/快捷键取消每行的注释。
比如要通过输入"mmain"自动补全if name==“main:”，并将鼠标光标另起一行，按下方修改相应的代码内容。

	"mmain": {
		"prefix": "mmain",//定义的快捷键mmain
		"body": [
			"if __name__==\"__main__\":", //自动补全的内容，因为我这里有双引号，要用转义字符"\"
			"$0"						//补全后的光标位置，如果这里没有"$0"，自动补全后的光标位置会在上一行的末尾
		],
		"description": "if __name__==\"__main__\": " //描述内容，因为我这里有双引号，要用转义字符"\"
	}
	

4. 完成后的内容如下，多条自动补全命令只要重复以上操作，加到前一条的“}”的后面

{
	// Place your snippets for python here. Each snippet is defined under a snippet name and has a prefix, body and 
	// description. The prefix is what is used to trigger the snippet and the body will be expanded and inserted. Possible variables are:
	// $1, $2 for tab stops, $0 for the final cursor position, and ${1:label}, ${2:another} for placeholders. Placeholders with the 
	// same ids are connected.
	// Example:
	// "Print to console": {
	// 	"prefix": "log",
	// 	"body": [
	// 		"console.log('$1');",
	// 		"$2"
	// 	],
	// 	"description": "Log output to console"
	// }
	"mmain": {
		"prefix": "mmain",
		"body": [
			"if __name__==\"__main__\":",
			"$0"				
		],
		"description": "if __name__==\"__main__\": "
	}
}