Implements the binary search algorithm in Python 3

binary_search.py

def sort(l):
    """
    Sorts a list
    :param l:
    :return: l_sorted
    """
    l_copy = l.copy()
    l_sorted = []
    for i in range(0, len(l_copy)):
        minimum = reduce(min, l_copy)
        # print(minumum)
        l_sorted.append(minimum)
        l_copy.remove(minimum)
    return l_sorted


def binary_search(list_, key, low=0, high=0):
    """
    Uses the binary search method to search through a sorted ist
    Returns -1 if not found
    :param list_: list
    :param key: integer
    :param low: integer
    :param high: length of list_
    :return: an index i or -1
    """
    if high < low:
        return low-1
    if high == 0:
        high = len(list_)
    mid = low + int(((high - low) / 2))
    try:
        _ = list_[mid]
    except IndexError:
        return -1
    if key == list_[mid]:
        return mid
    elif key < list_[mid]:
        return binary_search(list_, key, high=mid - 1, low=low)
    else:
        return binary_search(list_, key, low=mid + 1, high=high)