字典与键/值对

Question

I understand that a dictionary refers to a collection of key/value pairs, but I'm confused on a few of the finer details.

Does a dictionary need to contain more than one key value pair? Example 1:

person = {'first_name': 'John’} 

Is this a dictionary even though it only has 1 key & 1 value? Or would it need at least a 2nd key/value pair to really quality

Also, dictionaries seem very common in an API context. Here are some other examples/question I have. Example 2:

'itemFilter': [
    {'name': 'Condition', 'value': 'New'}
]       

Is this a dictionary? A list of dictionaries? Or is it a list of key value pairs. Wouldn't a list of dictionaries be something like:

list_of_dicts = [{‘key1’:’value1’},{‘key2’:’value2’}]

Also, does it need to have the '=' to be considered a dict / list of dicts? Or does the colon suffice here

Example 3:

 'paginationInput': {
        'entriesPerPage': 10,
        'pageNumber': 1
    }

Is this 2 dictionaries? Or a single dictionary with 2 key/value pairs. Im inclined to think it is the latter, since there is only one set of brackets denoted therein

Answer 1

Technically you can have an empty dictionary :

empty_dictionary = {}
empty_dictionary = dict()

So, no, a dictionary doesn't need to include multiple key value pairs.

Your second example is a list that has a single item which is a dictionary. A list also can have a single item, I hope that answers your next question.

Yes, you need to use the assignment operator of = to define your dictionary with that syntax.

paginationInput = {
        'entriesPerPage': 10,
        'pageNumber': 1
    }