python中将 \\uxxxx转换为 Unicode字符串

今天碰到一个很有意思的问题，需要将普通的 Unicode字符串转换为 Unicode编码的字符串，如下：

将 \\u9500\\u552e 转化为 \u9500\u552e 也就是 销售 。

乍一看感觉挺简单的，用 re 库将前面的反斜杠去掉即可，但是在替换的过程中会抛出如下错误：

Traceback (most recent call last):
  File "<pyshell#15>", line 1, in <module>
    re.sub(r"(\)\u", r'', t)
  File "D:\Python36\lib\re.py", line 191, in sub
    return _compile(pattern, flags).sub(repl, string, count)
  File "D:\Python36\lib\re.py", line 301, in _compile
    p = sre_compile.compile(pattern, flags)
  File "D:\Python36\lib\sre_compile.py", line 562, in compile
    p = sre_parse.parse(p, flags)
  File "D:\Python36\lib\sre_parse.py", line 855, in parse
    p = _parse_sub(source, pattern, flags & SRE_FLAG_VERBOSE, 0)
  File "D:\Python36\lib\sre_parse.py", line 416, in _parse_sub
    not nested and not items))
  File "D:\Python36\lib\sre_parse.py", line 765, in _parse
    p = _parse_sub(source, state, sub_verbose, nested + 1)
  File "D:\Python36\lib\sre_parse.py", line 416, in _parse_sub
    not nested and not items))
  File "D:\Python36\lib\sre_parse.py", line 502, in _parse