1.2 Python Data Structures, String, Date and Time

Question 1

A data structure in Python that is ordered and mutable (changeable)

Answer 1

List [ ]

Question 2

Items in this data structure do not need to be homogenous or of the same type

Answer 2

List

Question 3

Elements in this data structure are indexed according to a definite sequence and the indexing is done with 0 being the first index

Answer 3

List

Question 4

A list inside a list is called

Answer 4

Nested list

Question 5

It can have any number of items and they may be of different types (integer, float, string etc)

Answer 5

List

Question 6

The index of -1 refers to the last item, -2 to the second last item and so on

Answer 6

Negative indexing

Question 7

Add an element to the end of the list

Answer 7

append()

Question 8

Add all elements of a list to the end of another list

Answer 8

extend()

Question 9

Insert an item at the defined index

Answer 9

insert()

Question 10

Removes an item from the list

Answer 10

remove()

Question 11

Removes and returns an element at the given index

Answer 11

pop()

Question 12

Removes all items from the list

Answer 12

clear()

Question 13

Returns the index of the first matched item

Answer 13

index()

Question 14

Returns the count of number of items passed as an argument

Answer 14

count()

Question 15

Sort items in a list in ascending order

Answer 15

sort()

Question 16

Reverse the order of items in the list

Answer 16

reverse()

Question 17

Returns a shallow copy of the list

Answer 17

copy()

Question 18

This data structure is an unordered collection of items. Every element is unique (no duplicates) and immutable (cannot be changed)

Answer 18

Set { }

Question 19

Although a set element is immutable, a set itself is _____________. We can add or remove items from it

Answer 19

mutable

Question 20

A set cannot have mutable elements like lists, sets, or ______________ as its elements

Answer 20

dictionaries

Question 21

Adds an item to a set

Answer 21

add()

Question 22

Adds multiple items to a set

Answer 22

update()

Question 23

To remove an item in a set, use the remove() or _________ method

Answer 23

discard()

Question 24

If the item to remove does not exist in a set, __________ will raise an error

Answer 24

remove()

Question 25

If the item to remove does not exist, __________ will NOT raise an error

Answer 25

discard()

Question 26

Using ________ will remove the last item

Answer 26

pop()

Question 27

This method empties the set

Answer 27

clear()

Question 28

This keyword deletes the set completely

Answer 28

del

Question 29

Returns a new set with all items from both sets; symbolized by | operator

Answer 29

Union

Question 30

Returns a new set with Common Elements from both sets; symbolized by & operator

Answer 30

Intersection

Question 31

To find difference in between sets; symbolized by - operator

Answer 31

Difference

Question 32

To find difference from both sets; symbolized by ^ operator

Answer 32

Symmetric Difference

Question 33

A data structure in Python that is ordered and immutable (unchangeable)

Answer 33

Tuple ( )

Question 34

A tuple can be created without parentheses. This is called

Answer 34

tuple packing

Question 35

Ways to Access a Tuple

Answer 35

1. Postive Indexing 2. Negative Indexing 3. Slicing

Question 36

Returns the number of items (x) in a tuple

Answer 36

count(x)

Question 37

Returns the index of the first item that is equal to x

Answer 37

index(x)

Question 38

An unordered collection of items that is mutable

Answer 38

Dictionary

Question 39

____ of a dictionary must be unique and immutable data type such as strings, integers, and tuples

Answer 39

Keys

Question 40

This dictionary method returns None instead of KeyError, if the key is not found

Answer 40

get()

Question 41

This method removes an item with the provided key and returns the value

Answer 41

pop()

Question 42

This method can be used to remove and return an arbitrary (key, value) item pair from the dictionary

Answer 42

popitem()

Question 43

Returns a new dictionary with keys from seq and value equal to v (defaults to None)

Answer 43

fromkeys(seq[,v])

Question 44

Returns the value of the key. If the key doesn't exist, returns d (defaults to None)

Answer 44

get(key[,d])

Question 45

Return a new object of the dictionary's items in (key, value) format

Answer 45

item()

Question 46

Returns a new object of the dictionary's keys

Answer 46

keys()

Question 47

Removes the item with the key and returns its value or d if key is not found. If d is not provided and the key is not found, it raises KeyError

Answer 47

pop(key[,d])

Question 48

Returns the corresponding value if the key is in the dictionary. If not, inserts the key with a value of d and returns d (defaults to None)

Answer 48

setdefault[key[,d])

Question 49

Updates the dictionary with the key/value pairs from other, overwriting existing keys

Answer 49

update([other])

Question 50

Returns a new object of the dictionary's values

Answer 50

values()

Question 51

Returns True if all keys of the dictionary are True (or if the dictionary is empty)

Answer 51

all()

Question 52

Return True if any key of the dictionary is true. If the dictionary is empty, return False

Answer 52

any()

Question 53

Return the length of dictionary

Answer 53

len()

Question 54

Compares items of two dictionaries (Not available in Python 3)

Answer 54

cmp()

Question 55

Return a new sorted list of keys in the dictionary

Answer 55

sorted()

Question 56

Create a datetime object containing the current local date and time using this method

Answer 56

now()

Question 57

Use this method defined in the date class to get a date object containing the current local date

Answer 57

today()

Question 58

Commonly used classes in datetime module are:

Answer 58

- date Class - time Class - datetime Class - timedelta Class

Question 59

You can convert a timestamp to date using this method

Answer 59

fromtimestamp()

Question 60

A class from datetime module that contains information from both date and time objects

Answer 60

datetime.datetime Class

Question 61

Print year, month, hour, minute and timestamp

Answer 61

datetime.datetime Class

Question 62

Represents the difference between two dates or times

Answer 62

datetime.timedelta

Question 63

This method is defines under classes date, datetime and time. Creates a formatted string from a given date, datetime or time object. Ex.: %Y, %m, %d etc

Answer 63

strftime()