是否可以检测空请求？

Is it possible to see if the user requests "example.com/mypage/?" or "example.com/mypage/" ?

I would like to serve different content if the query string is symbol "?" is present in the request. Please note that there is no name or value (e.g. ?name=value) , just the request symbol "?". A solution in python would be excellent but php is acceptable too.

In PHP you can check if the REQUEST_URI ends in a ?. There are three different cases that might be of use to you:

if('?' === substr($_SERVER['REQUEST_URI'], -1)){
    // Empty query string with '?'
}else if(false === strpos($_SERVER['REQUEST_URI'], '?')){
    // No ? at all
}else{
    // Some query string exists (check $_GET)
}

Take the $_SERVER['REQUEST_URI'] and check if there is any question mark in it.

if(strpos($_SERVER['REQUEST_URI'], "?") >= 0) {
    //Question mark found
}

checking the last character

if ('?' === substr($_SERVER['REQUEST_URI'], -1))