Prevent CO_FUTURE_BARRY_AS_BDFL from being applied with PyCF_MASK

Bug report

Bug description:

When compiling Python strings with the PyCF_MASK, the CO_FUTURE_BARRY_AS_BDFL is included and will be applied to the statement. It would be preferable if the PEP 401 easter egg was not applied to code compiled with the PyCF_MASK compiler flag by default.

Example:

static const char code[] = "1 != 2";
static PyCompilerFlags compiler_flags = { PyCF_MASK | PyCF_SOURCE_IS_UTF8 };
PyObject* n = Py_CompileStringFlags(code, "<string>", Py_single_input, &compiler_flags);

Will result change the result to 1 <> 2.

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS, Windows

从 Include/cpython/compile.h 中 CO_FUTURE_BARRY_AS_BDFL 的定义开始，跟踪 Py_CompileStringFlags 如何处理 PyCF_MASK。在 CPython main 上复现所提供的 C 示例，然后添加或更新覆盖率测试，使 PyCF_MASK 默认不再应用 PEP 401 的行为。