Python

Question 1

What are the four data types in Python?

Answer 1

Lists, Tuples, Sets, and Dictionaries

Question 2

What is a List?

Answer 2

a collection which is ordered and changeable. Allows duplicate members. []

Question 3

What is a Tuple?

Answer 3

a collection which is ordered and unchangeable. Allows duplicate members.
( )

Question 4

What is a Set?

Answer 4

a collection which is unordered and unindexed. No duplicate members. { }

Question 5

What is a Dictionary?

Answer 5

a collection which is unordered, changeable and indexed. No duplicate members. {A: B }

Question 6

How do you access a List item?

Answer 6

list_name[Index]

Example:

thislist = [“apple”, “banana”, “cherry”]

print(thislist[1])

Question 7

How do you change an item in a list’s value?

Answer 7

list_name[Index] = “New Value”

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist[1] = “blackcurrant”
print(thislist)

Question 8

How do you loop through a List?

Answer 8

for x in list_name:
print(x)

Example:
thislist = [“apple”, “banana”, “cherry”]
for x in thislist:
print(x)

Question 9

How do you check if an item exists in a list?

Answer 9

if in

if “Carol”/2/22.3,etc. in list_name:
print(“Carol”/2/22.3,etc.)

Example:
thislist = [“apple”, “banana”, “cherry”]
if “apple” in thislist:
print(“Yes, ‘apple’ is in the fruits list”)

Question 10

How do you find the list’s length?

Answer 10

print(len(list_name))

Example:
thislist = [“apple”, “banana”, “cherry”]
print(len(thislist))

Question 11

How do you add items to the end of a list?

Answer 11

Use .append( ) Method

list_name.append(value)

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist.append(“orange”)
print(thislist)

Question 12

How do you add items to a list at a specified index?

Answer 12

Use .insert( ) Method

list_name.insert(index, value)

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist.insert(1, “orange”)
print(thislist)

Question 13

How do you remove a specific item from a List?

Answer 13

Use .remove( ) Method

list_name.remove(value)

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist.remove(“banana”)
print(thislist)

Question 14

How do you remove an item at a specified index?

Answer 14

Use the .pop( ) Method

list_name.pop(index value)

Note: if no index is inputted then it will be the last time of the list deleted.

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist.pop()
print(thislist)

Question 15

How do you delete a specific index from a list using a keyword?

Answer 15

Use the del keyword

del list_name[index]

Example:
thislist = [“apple”, “banana”, “cherry”]
del thislist[0]
print(thislist)

Question 16

How do you delete a whole list using a keyword?

Answer 16

Use the del keyword

del list_name

Example:
thislist = [“apple”, “banana”, “cherry”]
del thislist

Question 17

How do you empty a list?

Answer 17

Use the clear( ) Method

list_name.clear( )

Example:
thislist = [“apple”, “banana”, “cherry”]
thislist.clear()
print(thislist)

Question 18

How do you copy a list? (two ways)

Answer 18

Use the copy( ) Method
duplicated_list = original_list_name.copy( )

or

Use the list( ) Method

duplicated_list = list(originial_list_name)

Note: You cannot copy a list by typing list2 = list 1. This is because list2 will only be a reference to list1 and changes made in list1 will automatically also be made in list2.

.copy( ) Example:
thislist = [“apple”, “banana”, “cherry”]
mylist = thislist.copy()
print(mylist)

.list( ) Method Example:
thislist = [“apple”, “banana”, “cherry”]
mylist = list(thislist)
print(mylist)

Question 19

How do you make a new list?

Answer 19

Using the list( ) constructor

list((value,value,value,value))

Note: The double brackets

Example:
thislist = list((“apple”, “banana”, “cherry”)) # note the double round-brackets
print(thislist)

Question 20

Name the built-in methods for Lists

Answer 20

Method Description
append() Adds an element at the end of the list
clear() Removes all the elements from the list
copy() Returns a copy of the list
count() Returns the number of elements with the specified value
extend() Add the elements of a list (or any iterable), to the end of the current list
index() Returns the index of the first element with the specified value
insert() Adds an element at the specified position
pop() Removes the element at the specified position
remove() Removes the item with the specified value
reverse() Reverses the order of the list
sort() Sorts the list