How can I flatten nested data structures in Python?

How can I flatten nested data structures in Python?

You can use recursion or libraries like itertools to flatten nested lists or dictionaries. Would you like an example?

Yes, please provide an example using a nested list.

Sure! Here's a simple function to flatten a nested list:

def flatten(nested_list):
    flat_list = []
    for item in nested_list:
        if isinstance(item, list):
            flat_list.extend(flatten(item))
        else:
            flat_list.append(item)
    return flat_list

You can call it like this:

nested = [1, [2, [3, 4], 5], 6]
print(flatten(nested))  # Output: [1, 2, 3, 4, 5, 6]

What if I have a nested dictionary instead?

For a nested dictionary, you can use a different approach. Here's a function that flattens a nested dictionary:

def flatten_dict(nested_dict, parent_key='', sep='_'):
    items = []
    for k, v in nested_dict.items():
        new_key = f'{parent_key}{sep}{k}' if parent_key else k
        if isinstance(v, dict):
            items.extend(flatten_dict(v, new_key, sep=sep).items())
        else:
            items.append((new_key, v))
    return dict(items)

You can use it like this:

nested = {'a': 1, 'b': {'c': 2, 'd': 3}}
print(flatten_dict(nested))  # Output: {'a': 1, 'b_c': 2, 'b_d': 3}