Chapter 7

Question 1

What does list.append() do?

Answer 1

Add the contents of the brackets to the end of the list as one element

Question 2

What does list.extend() do?

Answer 2

Add a list to the end of the list

Question 3

What does list[x:x] = [1,2,3] do?

Answer 3

Add the list [1,2,3] at index x, move every value past index x down by one (including index x)

Question 4

what does list[x] = 1 do?

Answer 4

replace list[x] current value with 1

Question 5

What does list.insert(index,value) do?

Answer 5

inserts the value in list[index] while shuffling everything down one index, nothing is overwritten.
- Though .insert() does nest its contents, it doesn’t split it into separate indices
- e.g. list = [1,2,5,6]
- list.instert(2, [3,4])
- list = [1,2, [3,4], 5, 6]

Question 6

What does list.insert(len(list),val) do?

Answer 6

list.append(val)

Question 7

What is the output for x[::-1]
x = [1, 2, 3, 4, 5, 6]

Answer 7

[6, 5, 4, 3, 2, 1]

Question 8

How do you splice a list?

Answer 8

list[start : end : index step]
start included
end not included

Question 9

What does list[:] output?

Answer 9

The complete list

Question 10

What does list[::-2] output?

Answer 10

Every other element of the list, counting backwards

Question 11

What does list[-1] output?

Answer 11

Last character of the list

Question 12

What does list[-1:] output?

Answer 12

The last character of a list

Question 13

What does list.pop(index) do?

Answer 13

Deletes the value at the index in the list, can also be assigned to a variable while removing it from a list

Question 14

What does list.sort() do?

Answer 14

Sort the list in ascending order

Question 15

What does list.index(x) do?

Answer 15

returns the earliest index of value x

Question 16

What does del list[x] do?

Answer 16

Deletes the value in index x, shuffles everything in the list down an index

Question 17

How do you access elements in a dictionary?

Answer 17

element = dictionary[key]

Question 18

How do you loop through each key of a dictionary?

Answer 18

for key in dictionary:

Question 19

How do you get a value from a list in a dictionary?

Answer 19

dictionary[key][index in list]

e.g:
d = {‘x’ : 9,’y’ : 5, ‘z’ : [1,2,3]}
print(d[‘z’][2])

output:
3

Question 20

What does dictionary.get(x) do?

Answer 20

Get the value from key x in a dictionary

Question 21

How do you get each key:value pair form a dictionary?

Answer 21

for key, value in dictionary.items():
print(f’{key}:{value}’)

output:
key:value
….
….

Question 22

What does dictionary.items() do?

Answer 22

finds all key:value pairs in a dictionary,
- Can be used in a loop
- If assigned to a variable it will print a tuple called ‘dict_items’ filled with a list of each key:value pair

Question 23

How do you add a key:value pair to a dictionary?

Answer 23

dict[key] = value,
if key already exists, override current value

Question 24

How do you delete a key:value pair?

Answer 24

del dict[key]

Question 25

how do you edit a value in a dictionary?

Answer 25

dict[key] = new_value

Question 26

Can you do mathematical operations within a dictionary?

Answer 26

yes for example
a[‘c’] = 3
a[‘c’] +=3
print(a[‘c’])
output = 6

Question 27

What is the output?

mystr = “Howdy”
mylist = [2, 0, 2, 0]
mytuple = (mystr, mylist)
mylist[3] = 6
print(mytuple)

Answer 27

(‘Howdy’, [2, 0, 2, 6])
- The list is attached to the index, not the values of the list

Question 28

What does int(‘5.0’) result in?

Answer 28

It produces an error, ‘.’ cannot be converted into an integer

Question 29

Can you have a float in the range() function?

Answer 29

No, only integer values,
- Use a while loop if you want a floating step

Question 30

How do you use the range function to create a list?

Answer 30

a = list(range(a,b,c))

Question 31

What does list.remove(x) do?

Answer 31

Remove the earliest occurrence of value x from the list

Question 32

What are the restrictions on data types for a dictionary key?

Answer 32

Keys can only be any immutable data type:
- string
- tuple

Question 33

Which of these are tuples?
(1,2,3)
1, 2, 3
[1, 2, 3]

Answer 33

(1, 2, 3)
1, 2, 3

Question 34

How do you print a list or tuple without brackets or commas?

Answer 34

print(tuple)
print(list)

Question 35

How can you remove sections of a list?

Answer 35

a = [1,2,3,4,5,6,7]
a[:3] = []
print(a)
output = [4,5,6,7]