from typing import Sequence, Literal, Set, Tuple
from copy import deepcopy


def isNearlySorted(L: Sequence[float]) -> Literal[False] | Sequence[float]:
    """Returns a tuple of indices that need to be swapped to sort the list, or False if it cannot be sorted with a single swap."""
    if not len(L):
        return False
    sortPath: Set[Tuple[int, int]] = set()
    sortedList = list(deepcopy(L))
    for i in range(len(L) - 1):
        for j in range(len(L) - 1, i, -1):
            a = sortedList[i]
            b = sortedList[j]
            if a > b:
                sortedList[i], sortedList[j] = b, a
                sortPath.add((i, j))
    if len(sortPath) > 1:
        return False
    if len(sortPath) == 1:
        return list(sortPath.pop())
    return False


print("Testing isNearlySorted()...", end="")
assert isNearlySorted([2, 7, 5, 4]) == [1, 3]
assert isNearlySorted([2, 3, 1]) == False
assert isNearlySorted([1, 2, 3]) == False
assert isNearlySorted([-1, 1, 0, 5]) == [1, 2]
assert isNearlySorted([5, 6, 9, 8, 8]) == [2, 4]
assert isNearlySorted([2, 1]) == [0, 1]
assert isNearlySorted([3, 3]) == False
assert isNearlySorted([2]) == False
assert isNearlySorted([]) == False

# Verify that the function is non-mutating
L = [2, 7, 5, 4]
isNearlySorted(L)
assert L == [2, 7, 5, 4]
print("Passed!")