[flutter] Set the space between Elements in Row Flutter

To make an exact spacing, I use Padding. An example with two images:

Row(
    mainAxisAlignment: MainAxisAlignment.spaceAround,
    children: <Widget>[
      Expanded(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: Image.asset('images/user1.png'),
        ),
      ),
      Expanded(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: Image.asset('images/user2.png'),
        ),
      )
    ],
  ),