What will be the output of the following code?
my_list = [1, 2, 3]
my_list.append(4)
print(len(my_list))
append() adds one element to the list. Initial length is 3, after append(4) it becomes 4.
Which of the following is NOT a valid Python data type?
In Python, the string data type is represented as 'str', not 'string'. 'string' is not a built-in data type.
What will be the type of x after executing: x = [1, 2.5, 'hello']?
Square brackets [] create a list object. Lists in Python can contain elements of different data types (heterogeneous).
Which method removes and returns the last element from a list?
pop() removes and returns the last element (or element at specified index). remove() only removes value, doesn't return it.
What will be the output?
my_list = [1, 2, 3, 4, 5]
print(my_list[1:3])
List slicing [1:3] returns elements from index 1 (inclusive) to index 3 (exclusive), which are elements at positions 1 and 2.
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What is the output of: len([1, [2, 3], 4, [5, [6, 7]]])?
len() counts the number of top-level elements in the list: 1, [2,3], 4, and [5,[6,7]] = 4 elements total.
Which statement correctly creates a list of numbers from 1 to 5?
range(1, 6) generates 1 to 5 (exclusive end), and explicit list [1,2,3,4,5] both work. Both statements are correct.
What will be printed?
my_list = [10, 20, 30]
my_list[1] = 25
print(my_list)
Lists are mutable. Assignment my_list[1] = 25 changes the element at index 1 from 20 to 25.
Which of the following will return True?
my_list = [1, 2, 3]
result = 2 in my_list
The 'in' operator checks membership. Since 2 exists in my_list, the expression evaluates to True.
What is the difference between list and tuple in Python?
Lists (created with []) can be modified after creation, while tuples (created with ()) cannot be changed after initialization.
What will be the output?
my_list = [1, 2, 3]
my_list.extend([4, 5])
print(my_list)
extend() unpacks the iterable and adds individual elements. append() would add the list as a single element.
How many times will the value 2 appear in the output?
my_list = [1, 2, 2, 3, 2, 4]
print(my_list.count(2))
count() returns the number of occurrences of a value. The value 2 appears 3 times in the list.
What will be the output?
my_list = [[1, 2], [3, 4], [5, 6]]
print(my_list[1][0])
my_list[1] returns [3, 4], and [3, 4][0] returns 3 (first element of the nested list).
What will this code produce?
my_list = [3, 1, 4, 1, 5]
my_list.sort()
print(my_list)
sort() arranges list elements in ascending order by default. It modifies the list in-place.
What will be the output?
my_list = [1, 2, 3]
my_list_copy = my_list
my_list[0] = 99
print(my_list_copy[0])
Assignment creates a reference, not a copy. Both variables point to the same list object, so changes are reflected in both.
What is the correct way to create a true copy of a list?
Both .copy() method and list() constructor create shallow copies. Simple assignment creates only a reference.
What will be the output?
my_list = [1, 2, 3, 4, 5]
print(my_list[-2])
Negative indexing starts from the end: -1 is 5, -2 is 4, -3 is 3, etc. So -2 returns 4.
What will be the result of executing this code?
my_list = [1, 2, 3]
my_list.insert(1, 99)
print(my_list)
insert(1, 99) inserts 99 at index 1, shifting existing elements right. Result is [1, 99, 2, 3].
What will be printed?
my_list = [1, 2, 3, 4, 5]
print(my_list[::-1])
Slice [::-1] reverses the list by using step -1 (backwards through entire list). It returns a reversed copy.
