python - Why dict.get(key) instead of dict[key]?

Question

Today, I came across the dict method get which, given a key in the dictionary, returns the associated value.

For what purpose is this function useful? If I wanted to find a value associated with a key in a dictionary, I can just do dict[key], and it returns the same thing:

dictionary = {"Name": "Harry", "Age": 17}
dictionary["Name"]
dictionary.get("Name")

Answer 1

It allows you to provide a default value if the key is missing:

dictionary.get("bogus", default_value)

returns default_value (whatever you choose it to be), whereas

dictionary["bogus"]

would raise a KeyError.

If omitted, default_value is None, such that

dictionary.get("bogus")  # <-- No default specified -- defaults to None

returns None just like

dictionary.get("bogus", None)

would.