Chapter6

Question 1

What is dictionary in python?

Answer 1

A dictionary in Python is a collection of key-value pairs.

Question 2

what can be the key value?

Answer 2

Each key is connected to a value, and you can use a key to access the value associated with that key. A key’s value can be a number, a string, a list, or even another dictionary.In fact, you can use any object that you can create in Python as a value in a dictionary.

Question 3

What kind of object should be use as values in python?

Answer 3

In fact, you can use any object that you can create in Python as a value in a dictionary.

Question 4

How to create dictionary in python?

Answer 4

In Python, a dictionary is wrapped in braces, {}, with a series of key- value pairs inside the braces, as shown in the earlier example: alien_0 = {‘color’: ‘green’, ‘points’: 5}

Question 5

how to access values in dictionary?

Answer 5

alien_0 = {‘color’: ‘green’}

print(alien_0[‘color’])

Question 6

how to add New Key-Value Pairs?

Answer 6

a. Dictionaries are dynamic structures, and you can add new key-value pairs to a dictionary at any time
b. E.g alien_0[‘x_position’] = 0 alien_0[‘y_position’] = 25

Question 7

how to start with an empty dictionary?

Answer 7

alien_0 = {} 
alien_0['color'] = 'green'
alien_0['points'] = 5

Typically, you’ll use empty dictionaries when storing user-supplied data in a dictionary or when you write code that generates a large number of key-value pairs automatically.

Question 8

How to Modifying Values in a Dictionary?

Answer 8

To modify a value in a dictionary, give the name of the dictionary with the key in square brackets and then the new value you want associated with that key.

alien_0[‘color’] = ‘yellow’

Question 9

How to Remove Key-Value Pairs?

Answer 9

del alien_0[‘points’]

Question 10

How to create dictonary over many lines?

Answer 10

a. You can also use a dictionary to store one kind of information about many objects 
		favorite_languages = {
       'jen': 'python',
		       'sarah': 'c',
       'edward': 'ruby',
       'phil': 'python',
       }

b. When you know you’ll need more than one line to de ne a dictionary, press enter after the opening brace. Then indent the next line one level (four spaces), and write the rst key-value pair, followed by a comma. From this point forward when you press enter, your text editor should automatically indent all subsequent key-value pairs to match the rst key-value pair.
It’s good practice to include a comma after the last key-value pair as well, so you’re ready to add a new key-value pair on the next line.

Question 11

I am not sure if I finished , but checkd

Answer 11

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