Sometimes a struct field, function, type, or even a whole package becomes redundant or unnecessary,
but must be kept for compatibility with existing programs. To signal that an identifier should not be used,
add a paragraph to its doc comment that begins with “Deprecated:” followed by some information about the deprecation.
godoc accepts “Deprecated:” comments as a depected feature.
https://go.dev/blog/godoc
For example, https://pkg.go.dev/net/http/httputil#ClientConn