from array import array # python 提供的比较原始的 array 类arr = array('u', 'asdf')
print(arr[0], arr[1], arr[2], arr[3])
print(type([None] * 32))class Array(object):def __init__(self, size):self._size = sizeself._items = [None] * 32def __getitem__(self, item):return self._items[item]def __setitem__(self, key, value):self._items[key] = valuedef __len__(self):# return len(self._items)return self._sizedef __iter__(self):for i in self._items:yield idef clear(self):for i in range(len(self._items)):self._items[i] = Nonedef test_array():size = 10a = Array(size)a[0] = 1a[8] = 2assert a[0] == 1assert len(a) == 10assert a[8] == 2assert len(a) == 10