@function _shape-size-stripper($shape-size) {

$shape-size-spec: null;
@each $value in $shape-size {
  @if ($value == "cover") or ($value == "contain") {
    $value: null;
  }
  $shape-size-spec: "#{$shape-size-spec} #{$value}";
}
@return $shape-size-spec;

}