primitives Flashcards
What happens when you use end="!" in a print statement like print("Hello", end="!")?
It replaces the default newline character at the end of the print statement with “!”.
What’s the output of “yay!” if 0 > 1 else “nay!”?
“nay!”
What method adds an element to the end of a list?
list.append(element)
What’s the difference between li.append([5, 6]) and li.extend([5, 6])?
-
append()adds the entire object as a single element -
extend()adds each element of the iterable individually
How do you access the last element of a list in Python?
Using negative indexing: my_list[-1]
What does the slice notation some_list[1:3] return?
It returns a new list containing elements from index 1 up to (but not including) index 3.
What does the slice notation some_list[::2] do?
It returns every 2nd element from the list, starting from the first element.
What’s the primary difference between a tuple and a list in Python?
Tuples are immutable, while lists are mutable.
How do you create a tuple with just one element?
Include a trailing comma: (1,)
What does this code do? a, *b, c = (1, 2, 3, 4, 5)
It unpacks the tuple into variables: a gets 1, c gets 5, b gets [2, 3, 4].
What type of objects can be used as dictionary keys in Python?
Only immutable types like:
* Integers
* Floats
* Strings
* Tuples (if they contain only immutable types)
What happens if you try to access a key that doesn’t exist in a dictionary?
It raises a KeyError.
What’s the syntax to get a dictionary value with a default if the key doesn’t exist?
my_dict.get(key, default_value)
What’s the difference between dict.setdefault(key, value) and dict[key] = value?
setdefault() only sets the value if the key doesn’t already exist, while dict[key] = value always sets/updates the value.
How do you create an empty set in Python?
empty_set = set()
What happens if you add an element to a set that already contains that element?
Nothing changes. Sets only contain unique elements.
What set operation does the & symbol perform?
Intersection - returns elements that are common to both sets.
What set operation does the | symbol perform?
Union - returns all elements from both sets (without duplicates).
How do you check if an element exists in a set?
Use the in keyword.
How do you swap two variables in Python in a single line?
x, y = y, x
