functools

Higher-order functions and operations on callable objects.

import functools

Functions

functools.reduce(func: (T, T) -> T, iterable: list[T]) -> T

Apply function of two arguments cumulatively to the items of iterable, so as to reduce the iterable to a single value.

functools.reduce(func: (T, T) -> T, iterable: list[T], initial: T) -> T

Apply function of two arguments cumulatively to the items of iterable, starting with initial value.

functools.cmp_to_key(cmp: (T, T) -> int) -> IComparer[T]

Convert a comparison function into a key function for sorting. The comparison function should return a negative number for less-than, zero for equality, or a positive number for greater-than.