<s>[INST] # Python list with some of its elements as dictionaries

I have a list in Python which contains some dictionaries, and also other non-dictionary elements. For example:

```python
my_list = ['a', 1, {'key1': 'value1', 'key2': 'value2'}, 'b', {'key3': 'value3', 'key4': 'value4'}, 2, 'c']
```

Now I want to add some default value to the dictionaries in the list which are missing a certain key, say `'default'`.

How can I add a default value to the dictionaries which are missing the 'default' key?[/INST]