Built-in Functions and Lambdas Flashcards

What does `all([True, True, True])` return?

Answer: True

all() returns True only when every element in the iterable is truthy.

What is the result of `round(3.14159, 2)`?

Answer: 3.14

round() with ndigits=2 rounds the float to 2 decimal places, giving 3.14.

What does `enumerate(['a', 'b', 'c'], start=1)` produce?

Answer: (1,'a'), (2,'b'), (3,'c')

enumerate with start=1 pairs each element with an index beginning at 1 instead of 0.

What is the output of `list(zip([1,2,3], ['a','b','c']))`?

Answer: [(1,'a'), (2,'b'), (3,'c')]

zip pairs elements from each iterable at the same index into tuples.

Which built-in function converts a string to an integer?

Answer: int()

int() converts a string (or other numeric type) to an integer.

What does `sum([1, 2, 3], 10)` return?

Answer: 16

sum() accepts an optional start argument; it adds 1+2+3+10 = 16.

What does `len({'a': 1, 'b': 2, 'c': 3})` return?

Answer: 3

len() on a dictionary returns the number of key-value pairs.