getting all permutations in python with eval

permutation.py

# getting all permutations of N items in lst in python with eval
# iterable Int -> [(...) (...) ...]
def permute(lst, N):
    if N == 0 or N > len(lst):
        return []
    elif N < 0:
        raise ValueError('Second argument must be non-negative.')
    item = tuple(('i' + str(d) for d in range(N))) # tuple
    itemStr = '(' + ','.join(item) + ')' # str
    forSentence = ' '.join(' for ' + i + ' in _lst ' for i in item).replace('_lst', str(list(lst))) # str
    a = '[' + itemStr + forSentence + 'if len(set(' + itemStr + ')) == ' + str(N) + ']'
    return eval(a)
# eg: len(permute('1234', 3)) -> 24

# getting all permutations in lst
def permuteself(nums):
    if len(nums) == 0:
        return []
    from functools import reduce
    return [tuple(i) for i in reduce(lambda x, y: [str(a) + str(b) for a in x for b in y if str(b) not in str(a)], [nums] * len(nums))]