Doesn't return tag script attribute value

[Renan Bessa]

I'm trying to get the value of the data-ad-client attribute inside the script tag, but it's always null. Am I doing right?

adsense: {
          selector: 'script',
          attr: 'data-ad-client',
        },

[Ionică Bizău (Johnny B.)]

Can you please share a full example code? Make sure the script is present in the HTML.