How to use the wfdb.rdrecord function in wfdb

def process_data(filename):
    ecg_list = listdir(filename)
    sample_list = [ecg[:-4] for ecg in ecg_list]
    clean_sample_list = [ecg for ecg in sample_list if
                         ecg not in ['102-0', 'ANNOTA', 'REC', 'SHA256SUMS', 'mitd', 'x_m']]
    all_samples = np.zeros((len(clean_sample_list), 650000, 2))
    for idx, ecg in enumerate(clean_sample_list):
        record = wfdb.rdrecord(filename + ecg)
        all_samples[idx] = record.p_signal

    return all_samples

def _get_sections(self):
        """Collect continuous normal sinus rhythm sections."""
        # Empty dictionary for NSR sections
        sections = list()

        # Loop through recordings
        for record_id in self.record_ids:

            # Import recording
            record = wfdb.rdrecord(os.path.join(self.raw_path, record_id))

            # Import annotations
            annotation = wfdb.rdann(os.path.join(self.raw_path, record_id), 'atr')

            # Get sample frequency
            fs = record.__dict__['fs']

            # Get waveform
            waveform = record.__dict__['p_signal']

            # labels
            labels = np.array(annotation.__dict__['symbol'])

            # Samples
            sample = annotation.__dict__['sample']

def process_data(filename):
    ecg_list = listdir(filename) 
    sample_list = [ecg[:-4] for ecg in ecg_list]
    clean_sample_list = [ecg for ecg in sample_list if ecg not in ['102-0', 'ANNOTA', 'REC', 'SHA256SUMS', 'mitd', 'x_m']]    
    all_samples = np.zeros((len(clean_sample_list), 650000, 2))
    for idx, ecg in enumerate(clean_sample_list):
        record = wfdb.rdrecord(filename + ecg)
        all_samples[idx] = record.p_signal  
        
    return all_samples

def _get_sections(self):
        """Collect continuous arrhythmia sections."""
        # Empty dictionary for arrhythmia sections
        sections = list()

        # Loop through records
        for record_id in self.record_ids:

            # Import recording
            record = wfdb.rdrecord(os.path.join(self.raw_path, record_id))

            # Import annotations
            annotation = wfdb.rdann(os.path.join(self.raw_path, record_id), 'atr')

            # Get sample frequency
            fs = record.__dict__['fs']

            # Get waveform
            waveform = record.__dict__['p_signal']

            # labels
            labels = [label[1:] for label in annotation.__dict__['aux_note']]

            # Samples
            sample = annotation.__dict__['sample']

def process_data(filename):
    ecg_list = listdir(filename)
    sample_list = [ecg[:-4] for ecg in ecg_list]
    clean_sample_list = [ecg for ecg in sample_list if
                         ecg not in ['102-0', 'ANNOTA', 'REC', 'SHA256SUMS', 'mitd', 'x_m']]
    all_samples = np.zeros((len(clean_sample_list), 650000, 2))
    for idx, ecg in enumerate(clean_sample_list):
        record = wfdb.rdrecord(filename + ecg)
        all_samples[idx] = record.p_signal

    return all_samples