Accept ISO 8601 string, in addition to datetime/date/time object

Motivation:

I believe that the humanize functions are often used indrectly from template engines. In my case I use Jinja2 templating engine and the jinja2_humanize_extension, which relies on the humanize package.

{{ value | humanize_naturaldate }}

In many cases the underlying data (either a database, json-file or csv-file) stores/returns the datetime (or date or time) as a string, formatted in ISO8601 format. But in order to make humanize_naturaldate accept this, I need to first parse it.

{{ value | fromisoformat | humanize_naturaldate }}

The fromisoformat then needs to be set as a filter in the local or global jinja environment.

It would be great if humanize accepted these ISO8661 strings itself.

How to implement:

As far as I can tell, it would be very simple to implement and very simple to maintain. Every function callable by the client, that takes a datetime should start with:

if type(value) == str:
    try:
        value = datetime.datetime.fromisoformat(value)
    else:
        value = str

Similarly for date and time objects.

I will admit that I have only studied the code cursorily, and I might have missed some reasons why this is more complex than I currently believe it is.

首先定位接受 datetime、date 或 time 值的公共 humanize 函数，包括 humanize_naturaldate，并检查它们当前的输入处理方式。检查现有测试如何覆盖这些入口点。完成的标准是：受支持的 ISO 8601 字符串能够被一致地接受，同时现有的对象输入和无效值保留已定义的行为。