def blog__clean_category_parents
      category_parents = LatoBlog::CategoryParent.all
      category_parents.map { |cp| cp.destroy if cp.categories.empty? }
    end
def blog__clean_category_parents
      category_parents = LatoBlog::CategoryParent.all
      category_parents.map { |cp| cp.destroy if cp.categories.empty? }
    end
This function cleans all old category parents without any child.