func ACL(h http.Header, acl string) http.Header {
	if acl != "" {
		h.Set("x-amz-acl", acl)
	}
	return h
}
func ACL(h http.Header, acl string) http.Header {
	if acl != "" {
		h.Set("x-amz-acl", acl)
	}
	return h
}
func ACL ( h http . Header , acl string ) http . Header { if acl != " " { h . Set ( " " , acl ) } return h }
// add canned acl to http.Header
add canned acl to http . Header