def main(lst):
    new_lst = lst[:]
    for j in range(len(new_lst)):
        tmp = []
        for i in new_lst[j]:
            if i in tmp:
                continue
            elif i not in tmp and i is not None:
                a = i
                a = a.replace('[at]', '@')
                a = a.replace('Нет', 'N')
                a = a.replace('Да', 'Y')
                if a.replace('.', '').isdigit():
                    a = float(a)
                    a = "{:.4f}".format(a)
                if a not in tmp:
                    tmp.append(a)
        new_lst[j] = tmp
    tmp = []
    for i in range(len(new_lst)):
        if new_lst[i] in tmp:
            continue
        else:
            tmp.append(new_lst[i])
    return tmp


print(main([['Нет', None, None, 'kifin32[at]rambler.ru', '0.6', '0.6'],
            ['Да', None, None, 'zozorli58[at]gmail.com', '0.3', '0.3'],
            ['Нет', None, None, 'sototij87[at]yahoo.com', '0.2', '0.2'],
            ['Нет', None, None, 'sototij87[at]yahoo.com', '0.2', '0.2'],
            ['Нет', None, None, 'sototij87[at]yahoo.com', '0.2', '0.2']]))