def _ecg_band_pass_filter(data, sample_rate):
    """
    Bandpass filter with a bandpass setting of 5 to 15 Hz

    ----------
    Parameters
    ----------
    data : list
        List with the ECG signal samples.
    sample_rate : int
        Sampling rate at which the acquisition took place.

    Returns
    -------
    out : list
        Filtered signal.
    """
    nyquist_sample_rate = sample_rate / 2.
    normalized_cut_offs = [5/nyquist_sample_rate, 15/nyquist_sample_rate]
    b_coeff, a_coeff = butter(2, normalized_cut_offs, btype='bandpass')[:2]
    return filtfilt(b_coeff, a_coeff, data, padlen=150)