Open() on path that exceeds 248 char limit results in "FileNotFoundError: [Errno 2] No such file or directory"

Bug report

Attempting to open or appending paths to sys.path with paths that length exceed the 248 character limit results in incorrect errors. In the case of opening paths that exceeded the limit, rather than an error pointing to the path length being exceeded we see a file not found. A similar error handling issue is prevalent with appending paths that exceed the limit to sys.path. In this case when trying to access the module you will receive a module not found error. I am now aware the path limit can be disabled on installation or later but these false flags led me astray while debugging.

Reproduction Steps:

• Create a text file whose path exceeds 248 characters
• Attempt to read/write from that file
  or
• Create a Python module whose path exceeds 248 characters
• Attempt to import that module from an external directory by appending the path to sys.path

Environment

• CPython versions tested on: 3.10.4
• Operating system and architecture: Windows x64

首先在 Windows x64 和 Python 3.10.4 上复现报告的行为：打开路径超过 248 个字符的文件，然后测试从附加到 sys.path 的超长路径导入模块。跟踪打开和导入失败，以确定长度条件在哪个环节丢失。完成的标准是两种情况都报告准确的路径长度错误，而不是 FileNotFoundError 或 ModuleNotFoundError。