Bucket sort of List[int] in python

bs.py

"""
Bucket sort (of type List[int])
"""

from itertools import chain
from typing import List

def bucket_sort(somelist: List[int], n_buckets: int = None, approximate: bool = False):
    if n_buckets is None:
        n_buckets = int(len(somelist) ** 0.5)

    buckets = [list() for _ in range(n_buckets)]
    m = 1 + max(somelist)

    for i, item in enumerate(somelist):
        buckets[int(n_buckets * item / m)].append(item)

    if not approximate:
        for i, item in enumerate(buckets):
            item.sort()

    return list(chain(*buckets))

# examples
from random import randint, seed

seed(1234)

list_to_sort = [randint(1, 10) for _ in range(20)]

bucket_sort(list_to_sort)
bucket_sort(list_to_sort, approximate = True)