Beautiful soup4 gets the value of the class property of the tag

BeautifulSoup4 retrieves the value of the class attribute of the tag
Recently, when I was writing a crawler, I suddenly needed to determine whether the class value of the current tag was a specific value. After searching online, I found that it was not very helpful, so I made a note of it.
Using the GET method

html = BeautifulSoup(request,'lxml')
a = html.find_all('a')
for i in a:
	if (i.get('class') == 'xxx'):
		url = i.get('href')
		return url
return None

The above code has the following functions:

    converts the request to BS4 format and stores it in HTML to find all the A tags in HTML, traverse the A tag, and check whether the class value of the current A tag is equal to ‘XXX’. True will return the URL of the current A tag. If the traverse fails to match, it will return None
The get function does more than that. The arguments in get represent the name of the variable you want to get.