Coding challenge: find the repeated items in a collection of elements

A list of mixed types ['m', 'b', None, 'm', 'x', 'x', 'a', 'c', 3, None, 1, 2, 3, 4, 5, 6, 5, <__main__.Employee object at 0x7fa45044c470>, <__main__.Employee object at 0x7fa45044c470>, <__main__.Employee object at 0x7fa45044c5f8>]
Dictionary of items and their counts {1: 1, None: 2, 3: 2, 4: 1, 5: 2, 6: 1, <__main__.Employee object at 0x7fa45044c470>: 2, 'c': 1, 2: 1, 'x': 2, 'a': 1, 'b': 1, 'm': 2, <__main__.Employee object at 0x7fa45044c5f8>: 1}
The repeated items [None, 3, 5, <__main__.Employee object at 0x7fa45044c470>, 'x', 'm']