我应该如何更改此函数，以便它可以在 Python 2 和 Python 3 中巧妙地处理字符串和 unicode？

Question

我有一个向一个或多个收件人发送短信和文件的功能。在 Python 2 中有一个全局发送者对象，它接受文本和接收者配置作为 Python 2 中的 unicode 对象和 Python 3 中的字符串对象。这是现在的函数，并且与 Python 2 兼容：

def send_message_Telegram(
    recipient  = None, # string
    recipients = None, # list of strings
    text       = None,
    filepath   = None
    ):

    if text and not filepath:
        if recipient:
            tg_sender.send_msg(
                unicode(recipient),
                unicode(text)
            )
        if recipients:
            for recipient in recipients:
                tg_sender.send_msg(
                    unicode(recipient),
                    unicode(text)
                )
    if filepath and not text:
        if recipient:
            tg_sender.send_file(
                unicode(recipient),
                unicode(filepath)
            )
        if recipients:
            for recipient in recipients:
                tg_sender.send_file(
                    unicode(recipient),
                    unicode(filepath)
                )

如果我希望这个函数与 Python 3 兼容，我必须将 unicode() 的所有用法更改为 str()。我需要该函数在 Python 2 和 Python 3 中都可以工作，那么应该如何更改它呢？我不想到处写这样的代码：

if sys.version_info >= (3, 0):
    tg_sender.send_msg(
        str(recipient),
        str(text)
    )
else:
    tg_sender.send_msg(
        unicode(recipient),
        unicode(text)
    )

就像，这是我目前最好的，但看起来很奇怪：

def ustr(text):

    if text is not None:
        if sys.version_info >= (3, 0):
            return str(text)
        else:
            return unicode(text)
    else:
        return text

def send_message_Telegram(
    recipient  = None, # string
    recipients = None, # list of strings
    text       = None,
    filepath   = None
    ):

    if text and not filepath:
        if recipient:
            tg_sender.send_msg(
                ustr(recipient),
                ustr(text)
            )
        if recipients:
            for recipient in recipients:
                tg_sender.send_msg(
                    ustr(recipient),
                    ustr(text)
                )
    if filepath and not text:
        if recipient:
            tg_sender.send_file(
                ustr(recipient),
                ustr(filepath)
            )
        if recipients:
            for recipient in recipients:
                tg_sender.send_file(
                    ustr(recipient),
                    ustr(filepath)
                )

Answer 1

您可以只创建一个函数来安全地转换字符串。

这将是我的解决方案：

def string(data):
    if sys.version_info >= (3, 0):
        return str(data)
    else:
        return unicode(data)

Answer 2

函数的别名如何取决于版本？：

def send_message_Telegram(recipient  = None, 
                          recipients = None, 
                          text = None,
                          filepath = None):
    if sys.version_info[0] < 3:
        func = unicode
    else:
        func = str

    # the rest here, using 'func()'

Answer 3

如果你安装了the six module，你可以使用它的text_type来引用2.x中的unicode和3.x中的str。