public void MapsGuids()
        {
            var interestId    = Guid.NewGuid();
            var replacementId = Guid.NewGuid();
            var guidMap       = new Dictionary <Guid, Guid>
            {
                { interestId, replacementId }
            };
            var entity = new Entity
            {
                Id          = Guid.NewGuid(),
                LogicalName = "contact",
                Attributes  = new AttributeCollection
                {
                    { "interest", new EntityReference("interest", interestId) }
                }
            };

            Assert.AreNotEqual(replacementId, entity.GetAttributeValue <EntityReference>("interest").Id);

            DataWriterService.MapEntityGuids(entity, guidMap);

            Assert.AreEqual(replacementId, entity.GetAttributeValue <EntityReference>("interest").Id);
        }