Ch 9
What is the number of the first index in a dictionary?
Dictionaries are not indexed by number.
Sets are created using curly braces { }.
False
Sets are immutable.
False
The elements in a dictionary are stored in ascending order, by the keys of the key-value pairs.
False
The union of two sets is a set that contains only the elements that appear in both sets.
False
What does the get method do if the specified key is not found in the dictionary?
It returns a default value.
What will be the result of the following code? ages = {'Aaron' : 6, 'Kelly' : 3, 'Abigail' : 1 } value = ages['Brianna']
KeyError
Which of the following does not apply to sets?
The elements are in pairs.
A dictionary can include the same value several times but cannot include the same key several times.
True
If you try to retrieve a value from a dictionary using a nonexistent key, a KeyError exception is raised.
True
The difference of set1 and set2 is a set that contains only the elements that appear in set1 but do not appear in set2.
True
The issubset() method can be used to determine whether set1 is a subset of set2.
True
The set remove and discard methods behave differently only when a specified item is not found in the set.
True
You would typically use a for loop to iterate over the elements in a set.
True
In order to avoid KeyError exceptions, you can check whether a key is in the dictionary using the ________ operator.
in
Which method would you use to get all the elements in a dictionary returned as a list of tuples?
items
In a dictionary, you use a(n) ________ to locate a specific value.
key
Which would you use to get the number of elements in a dictionary?
len
What is the process used to convert an object to a stream of bytes that can be saved in a file?
pickling
Which method would you use to get the value associated with a specific key and remove that key-value pair from the dictionary?
pop
What is the correct structure to create a dictionary of months where each month will be accessed by its month number (for example, January is month 1, April is month 4)?
{ 1 : 'January', 2 : 'February', ... 12 : 'December' }
1. What will be displayed after the following code executes? (Note: the order of the display of entries in a dictionary are not in a specific order.) cities = {'GA' : 'Atlanta', 'NY' : 'Albany', 'CA' : 'San Diego'} if 'CA' in cities: del cities['CA'] cities['CA'] = 'Sacramento' print(cities)
{'CA': 'Sacramento', 'NY': 'Albany', 'GA': 'Atlanta'}
What will be displayed after the following code executes? (Note: the order of the display of entries in a dictionary are not in a specific order.) cities = {'Ga':'Atl','NY':'Alb','CA':'San D'} if 'FL' in cities: del cities['FL'] cities['FL']='Tallah' print(cities)
{'CA': 'San Diego', 'NY': 'Albany', 'GA': 'Atlanta'}
