When using the main branch, I found that some changed code didn't have comments. This PR adds some comments.  | 
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|---|---|---|
| .. | ||
| httpcache.go | ||
| httpcache_test.go | ||
				
					
						
							When using the main branch, I found that some changed code didn't have comments. This PR adds some comments.  | 
			||
|---|---|---|
| .. | ||
| httpcache.go | ||
| httpcache_test.go | ||