Python 正则表达式：当后跟字母时，在数字后添加空格

在一组数字之后，我想在字符串中添加一个空格。例如，以下字符串应在数字后添加空格：

Before                           After
"0ABCD TECHNOLOGIES SERVICES"    "0 ABCD TECHNOLOGIES SERVICES"
"ABCD0 TECHNOLOGIES SERVICES"    "ABCD 0 TECHNOLOGIES SERVICES"

"ABCD 0TECHNOLOGIES SERVICES"    "ABCD 0 TECHNOLOGIES SERVICES"
"ABCD TECHNOLOGIES0 SERVICES"    "ABCD TECHNOLOGIES 0 SERVICES"

"ABCD TECHNOLOGIES 0SERVICES"    "ABCD TECHNOLOGIES 0 SERVICES"
"ABCD TECHNOLOGIES SERVICES0"    "ABCD TECHNOLOGIES SERVICES 0"

我一直在尝试用Python处理正则表达式，如下所示：

text= re.sub(r'([0-9]+)?([A-Za-z]+)?([0-9]+)?',
             r'\1 \2 \3',
             text,
             0,
             re.IGNORECASE)

在前面的代码中，我得到了影响其他正则表达式转换的不需要的空格：

"0 abcd     technologies     services   "

如何在不添加不需要的空格的情况下在字符串中添加空格？

您可以使用

re.sub(r'(?<=\d)(?=[^\d\s])|(?<=[^\d\s])(?=\d)', ' ', text)

输出：

0 ABCD TECHNOLOGIES SERVICES
ABCD 0 TECHNOLOGIES SERVICES
ABCD 0 TECHNOLOGIES SERVICES
ABCD TECHNOLOGIES 0 SERVICES
ABCD TECHNOLOGIES 0 SERVICES
ABCD TECHNOLOGIES SERVICES 0

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非常感谢您的解释：）

0 ABCD TECHNOLOGIES SERVICES
ABCD 0 TECHNOLOGIES SERVICES
ABCD 0 TECHNOLOGIES SERVICES
ABCD TECHNOLOGIES 0 SERVICES
ABCD TECHNOLOGIES 0 SERVICES
ABCD TECHNOLOGIES SERVICES 0