Why Does Python Throw a `TypeError: Unhashable Type \'dict\'` and How to Fix It?

TypeError: Unhashable Type 'dict'

In Python, certain objects such as dictionaries cannot be used as keys in a dictionary or set because they are not hashable. Hashable objects have a constant value and can be used as keys to quickly retrieve data from a dictionary or set.

To resolve this error, you need to convert the problematic dictionary (dict_key) into a hashable object. One way to do this is by creating a frozenset from the dictionary's items.

<code class="python">key = frozenset(dict_key.items())</code>

This frozenset can now be used as a key in a dictionary or set:

<code class="python">if key in some_dict:
    print("Key exists in the dictionary")</code>

Note that this freezing process may need to be applied recursively if the dictionary values themselves contain other unhashable objects.

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