public Person Build()
        {
            string   firstName  = firstNameBuilder.Build();
            string   middleName = middleNameBuilder.Build();
            string   lastName   = lastNameBuilder.Build();
            Gender?  sex        = genderBuilder.Build();
            int?     age        = ageBuilder.Build();
            DateTime?birthDate  = age == null?birthDateBuilder.Build() : birthDateBuilder.BuildWithParams(age.Value);

            string country     = countryBuilder.Build();
            string email       = emailBuilder.BuildWithParams(firstName, lastName, age.ToString());
            string phoneNumber = phoneNumberBuilder.Build();

            return(new Person
            {
                FirstName = firstName,
                MiddleName = middleName,
                LastName = lastName,
                Sex = sex,
                Age = age,
                BirthDate = birthDate,
                Country = country,
                Email = email,
                PhoneNumber = phoneNumber
            });
        }