title: How do we find duplicates in a list of objects
body: <p>How do we find duplicates in a list of objects based on multiple properties?</p>
  
  <p>The following code is not returning if the list contains dupes or not.</p>
  
  <pre><code>var dups = ListItems.GroupBy(i =&gt; new { i.Value, i.Code })
                      .Where(g =&gt; g.Count() &gt;= 1)
                      .Select(g =&gt; new 
                       { 
                          Length = g.Key.Value,
                          Label = g.Key.Code,
                          Count = g.Count()
                        });
  </code></pre>