关于python 3.x：是否有一种pythonics方法可以将Sequences对象（如“tuple和list”）与Sequence对象（如“bytes和str”）区分开来

is there a pythonics way to distinguish Sequences objects like “tuple and list” from Sequence objects like “bytes and str”

我有这样的功能

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def print_stuff(items):
if isinstance(items, (str, bytes)):
items = (items,)
for item in items:
print (item)

可称为：

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In [37]: print_stuff(('a', 'b'))
a
b

In [38]: print_stuff('a')
a

我不喜欢做isinstance (items, (str, bytes))，我更喜欢做isinstance(item, (collections.abc.MAGIC))。

其中magic是可以包含其他序列对象的所有序列对象的ABC，例如

元组
列表
编号数组
一些用户定义的向量类等

但不是：

STR
字节
一些用户定义的用于UTF-16等的str类

恐怕这是不可能的，因为tuple和str有相同的7个ABC：(

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In [49]: [v for k, v in vars(collections.abc).items()
...: if inspect.isclass(v) and issubclass(tuple, v) ]
Out[49]:
[collections.abc.Hashable,
collections.abc.Iterable,
collections.abc.Reversible,
collections.abc.Sized,
collections.abc.Container,
collections.abc.Collection,
collections.abc.Sequence]

In [50]: [v for k, v in vars(collections.abc).items()
...: if inspect.isclass(v) and issubclass(list, v) ]
Out[50]:
[collections.abc.Iterable,
collections.abc.Reversible,
collections.abc.Sized,
collections.abc.Container,
collections.abc.Collection,
collections.abc.Sequence,
collections.abc.MutableSequence]

In [51]: [v for k, v in vars(collections.abc).items()
...: if inspect.isclass(v) and issubclass(str, v) ]
Out[51]:
[collections.abc.Hashable,
collections.abc.Iterable,
collections.abc.Reversible,
collections.abc.Sized,
collections.abc.Container,
collections.abc.Collection,
collections.abc.Sequence]