Function _is_musl

tests/env.py:20–22

()

if LINUX:

    def _is_musl() -> bool:
        libc, _ = platform.libc_ver()
        return libc == "musl" or (libc != "glibc" and libc != "")

    MUSLLINUX = _is_musl()
    MANYLINUX = not MUSLLINUX