How to read static property of an ES6 class within its instance?

Question

How can i read the static properties of a class inside an instance of that class ? More specifically in the mixin (but this doesn't change the main answer)

Main component:

class A extends mixin(LitElement) {
 static get prop() { return 'a' }
}

window.customElements.define('tag', A)

Mixin:

export default (Parent) =>
 return class extends Parent {
  constructor() {
   super()
   // Here i want to access the `prop` return value from Parent
  }

  method() {
   // Or here
  }
 }

I tried a lot of possibilities, for example with eval(`${this.constructor.name}.properties`) but they do not work :(

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