Why do Python's math.ceil() and math.floor() operations return floats instead of integers?

Question

Can someone explain this (straight from the docs- emphasis mine):

math.ceil(x) Return the ceiling of x as a float, the small

Answer 1

As pointed out by other answers, in python they return floats probably because of historical reasons to prevent overflow problems. However, they return integers in python 3.

>>> import math
>>> type(math.floor(3.1))

>>> type(math.ceil(3.1))

You can find more information in PEP 3141.