How do I bring up a dialog to let the user choose an asset?

I am writing an editor script that allows the user to set all the Physic materials on the selected objects' colliders. What is the easiest way to bring up a dialog to let the user choose the material? Preferably, I would like to use the same dialog that Unity uses, i.e. this one:

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Just have a public field inside your custom inspector or wizard or whatever. When the user clicks it to choose the material, the dialog will pop up. As far as I know, there's no way to just "show" that dialog, you need to do it through an inspector or editor window or wizard.

EdiorUtility.OpenFilePanel()