public Relationship CreateRelationshipTo(Node node, string relationShipType)
{
if ((this.GetLocation()==null) || (node.GetLocation()==null))
throw new Exception("Parent or child node is not created. Create both node before creating the relation");
Relationship relationShip = new Relationship(this, node, relationShipType);
return _relationShipRepo.CreateRelationship(this, relationShip);
}