public void Sim_IsCall()
        {
            // Arrange / Act
            IOutput  output  = new OutputMock();
            ISimCard simcard = new Sim(output);

            simcard.Call(output);

            var expectedString = "Sim call";
            var myOutput       = output.Output.ToString();

            //Assert
            Assert.AreNotEqual(expectedString, myOutput);
            Assert.IsTrue(myOutput.Contains(expectedString));
        }