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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def acquire_nix(lock_file):
 # pragma: no cover """Acquire a lock file on linux or osx."""

    fd = os.open(lock_file, OPEN_MODE)

    try:
        fcntl.flock(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
    except (IOError, OSError):
        os.close(fd)
    else:
        return fd