Know if mixin is being called from within a media query

I need to do a check in a mixin, to know if it's being called from within a media query. Do you have a way?

@mixin teste {

  @if [esta dentro de media?] {
    ...
  } @else {
    ...
  }

}

@media (min-width: 768px) {
  @include teste;
}