def iter_find(_str, to_find, n=0):
    """ Finds all occurences of `to_find` in `_str`. Itering-ready. """
    _str_len = len(_str)
    to_find_len = len(to_find)
    while n <= _str_len:
        if _str[n:n+to_find_len] == to_find:
            yield n
        n += 1
 Finds all occurences of `to_find` in `_str`. Itering-ready. 
recipes/Python/576715_REAL_case_insensitive_string/recipe-576715.py