human
Can you provide a the Python program you requested given the following:
Complete the below
def gen(max_len, how_many):

    ''''Generate some programs.'
    '''
assistant
#Here is the Python program you requested.
    functions = [f_head, f_last, f_take, f_drop, f_access, f_max, f_min, f_reverse, f_sort, f_sum, f_map, f_filter, f_count, f_zipwith, f_scan]
    types_to_lambdas = {FunctionType(['Int', 'Int']): ['plus_one', 'minus_one', 'times_two', 'div_two', 'sq', 'times_three', 'div_three', 'times_four', 'div_four'], FunctionType(['Int', 'Bool']): ['pos', 'neg', 'even', 'odd'], FunctionType(['Int', 'Int', 'Int']): ['add', 'sub', 'mul']}
    tokens = []
    for f in functions:
        tokens.append(f.name)
    for v in types_to_lambdas.values():
        tokens.extend(v)
    tokens.extend(['=', ';', ',', '(', ')', '[', ']', 'Int', 'out'])
    tokens.extend(map(chr, range(97, 123)))
    io_tokens = map(str, range((-220), 220))
    if (not prog_vocab):
        prog_vocab.extend(((['_PAD', '_EOS'] + tokens) + io_tokens))
        for (i, t) in enumerate(prog_vocab):
            prog_rev_vocab[t] = i
    io_tokens += [',', '[', ']', ')', '(', 'None']
    grower = ProgramGrower(functions=functions, types_to_lambdas=types_to_lambdas)
    def mk_inp(l):
        return [random.choice(range((-5), 5)) for _ in range(l)]
    tar = [ListType('Int')]
    inps = [[mk_inp(3)], [mk_inp(5)], [mk_inp(7)], [mk_inp(15)]]
    save_prefix = None
    outcomes_to_programs = dict()
    tried = set()
    counter = 0
    choices = ([0] if (max_len == 0) else range(max_len))
    while ((counter < (100 * how_many)) and (len(outcomes_to_programs) < how_many)):
        counter += 1
        length = random.choice(choices)
        t = grower.grow(length, tar)
        while (t in tried):
            length = random.choice(choices)
            t = grower.grow(length, tar)
        tried.add(t)
        outcomes = [clean_up(t.evaluate(i)) for i in inps]
        outcome_str = str(zip(inps, outcomes))
        if (outcome_str in outcomes_to_programs):
            outcomes_to_programs[outcome_str] = min([t.flat_str(), outcomes_to_programs[outcome_str]], key=(lambda x: len(tokenize(x, tokens))))
        else:
            outcomes_to_programs[outcome_str] =...