def METHOD_NAME():
    """Test inferring a correct EEG placement scheme."""
    # no eeg channels case (e.g., MEG data)
    data_path = op.join(base_path, "bti", "tests", "data")
    raw_fname = op.join(data_path, "test_pdf_linux")
    config_fname = op.join(data_path, "test_config_linux")
    headshape_fname = op.join(data_path, "test_hs_linux")
    raw = mne.io.read_raw_bti(raw_fname, config_fname, headshape_fname)
    placement_scheme = _infer_eeg_placement_scheme(raw)
    assert placement_scheme == "n/a"
    # 1020 case
    data_path = op.join(base_path, "brainvision", "tests", "data")
    raw_fname = op.join(data_path, "test.vhdr")
    raw = mne.io.read_raw_brainvision(raw_fname)
    placement_scheme = _infer_eeg_placement_scheme(raw)
    assert placement_scheme == "based on the extended 10/20 system"
    # Unknown case, use raw from 1020 case but rename a channel
    raw.rename_channels({"P3": "foo"})
    placement_scheme = _infer_eeg_placement_scheme(raw)
    assert placement_scheme == "n/a"