public void Adds_Custom_Taxonomy_To_HashSet()
    {
        // Arrange
        var name = Rnd.Str;
        var type = new Taxonomy(name);

        // Act
        var result = Taxonomy.AddCustomTaxonomy(type);

        // Assert
        Assert.True(result);
        Assert.Contains(Taxonomy.AllTest(),
                        x => x.Equals(type)
                        );
    }
    public void Does_Not_Add_Custom_Taxonomy_Twice()
    {
        // Arrange
        var name = Rnd.Str;
        var type = new Taxonomy(name);

        Taxonomy.AddCustomTaxonomy(type);

        // Act
        var result = Taxonomy.AddCustomTaxonomy(type);

        // Assert
        Assert.False(result);
        Assert.Contains(Taxonomy.AllTest(),
                        x => x.Equals(type)
                        );
    }