How to use the niscope.VerticalCoupling function in niscope

def test_read(session):
    test_voltage = 1.0
    test_record_length = 2000
    test_channels = range(2)
    test_num_channels = 2
    test_num_records = 3
    session.configure_vertical(test_voltage, niscope.VerticalCoupling.AC)
    session.configure_horizontal_timing(50000000, test_record_length, 50.0, test_num_records, True)
    waveforms = session.channels[test_channels].read(num_samples=test_record_length, num_records=test_num_records)
    assert len(waveforms) == test_num_channels * test_num_records
    for i in range(len(waveforms)):
        assert len(waveforms[i].samples) == test_record_length

def example(resource_name, options, total_acquisition_time_in_seconds, voltage, sample_rate_in_hz, samples_per_fetch):
    total_samples = int(total_acquisition_time_in_seconds * sample_rate_in_hz)
    # 1. Opening session
    with niscope.Session(resource_name=resource_name, options=options) as session:
        # We will acquire on all channels of the device
        channel_list = [c for c in range(session.channel_count)]  # Need an actual list and not a range

        # 2. Creating numpy arrays
        waveforms = [np.ndarray(total_samples, dtype=np.float64) for c in channel_list]

        # 3. Configuring
        session.configure_horizontal_timing(min_sample_rate=sample_rate_in_hz, min_num_pts=1, ref_position=0.0, num_records=1, enforce_realtime=True)
        session.channels[channel_list].configure_vertical(voltage, coupling=niscope.VerticalCoupling.DC, enabled=True)
        # Configure software trigger, but never send the trigger.
        # This starts an infinite acquisition, until you call session.abort() or session.close()
        session.configure_trigger_software()
        current_pos = 0
        # 4. initiating
        with session.initiate():
            while current_pos < total_samples:
                # We fetch each channel at a time so we don't have to de-interleave afterwards
                # We do not keep the wfm_info returned from fetch_into
                for channel, waveform in zip(channel_list, waveforms):
                    # 5. fetching - we return the slice of the waveform array that we want to "fetch into"
                    session.channels[channel].fetch_into(waveform[current_pos:current_pos + samples_per_fetch], relative_to=niscope.FetchRelativeTo.READ_POINTER,
                                                         offset=0, record_number=0, num_records=1, timeout=hightime.timedelta(seconds=5.0))
                current_pos += samples_per_fetch