How does defaultdict work?

• defaultdict will automatically create a dictionary for you that has keys which are the integers 0-10.
• defaultdict forces a dictionary to only accept keys that are of the types specified when you created the defaultdict (such as string or integers).
• If you try to access a key in a dictionary that doesn’t exist, defaultdict will create a new key for you instead of throwing a KeyError.
• defaultdict stores a copy of a dictionary in memory that you can default to if the original gets unintentionally modified.

or

• defaultdict will automatically create a dictionary for you that has keys which are the integers 0-10.
• defaultdict forces a dictionary to only accept keys that are of the types specified when you created the defaultdict (such as strings or integers).
• If you try to read from a defaultdict with a nonexistent key, a new default key-value pair will be created for you instead of throwing a KeyError.
• defaultdict stores a copy of a dictionary in memory that you can default to if the original gets unintentionally modified.