问Python中的指针？

EN

>>> a = 1
>>> b = a # modify this line somehow so that b "points to" a
>>> a = 2
>>> b
1

<?php

class Form {
    public $data = [];
    public $fields;

    function __construct($fields) {
        $this->fields = $fields;
        foreach($this->fields as &$field) {
            $this->data[$field['id']] = &$field['value'];
        }
    }
}

$f = new Form([
    [
        'id' => 'fname',
        'value' => 'George'
    ],
    [
        'id' => 'lname',
        'value' => 'Lucas'
    ]
]);

echo $f->data['fname'], $f->fields[0]['value']; # George George
$f->data['fname'] = 'Ralph';
echo $f->data['fname'], $f->fields[0]['value']; # Ralph Ralph

GeorgeGeorgeRalphRalph

#include <iostream>
using namespace std;

int main() {
    int* a;
    int* b = a;
    *a = 1;
    cout << *a << endl << *b << endl; # 1 1

    return 0;
}