How do I add a key to a dictionary in Python?

How do I add a key to a dictionary in Python?

You can add a key to a dictionary by using the syntax dict[key] = value. For example, my_dict['new_key'] = 'new_value'.

What if the key already exists?

If the key already exists, assigning a new value will overwrite the existing value. For example, my_dict['existing_key'] = 'new_value' will change the value of 'existing_key'.

Can I add multiple keys at once?

Yes, you can use the update() method to add multiple keys. For example, my_dict.update({'key1': 'value1', 'key2': 'value2'}).

What happens if I try to add a key with a non-hashable type?

You will get a TypeError. Dictionary keys must be of a hashable type, like strings, numbers, or tuples.