code: def _acceptpeak(peak, amp, definitive_peaks, spk1, rr_buffer):
      
  
      definitive_peaks_out = definitive_peaks
      definitive_peaks_out = numpy.append(definitive_peaks_out, peak)
      spk1 = 0.125 * amp + 0.875 * spk1  # spk1 is the running estimate of the signal peak
      if len(definitive_peaks_out) > 1:
          rr_buffer.pop(0)
          rr_buffer += [definitive_peaks_out[-1] - definitive_peaks_out[-2]]
  
      return numpy.array(definitive_peaks_out), spk1, rr_buffer
docs: Private function intended to insert a new RR interval in the buffer.
  
      ----------
      Parameters
      ----------
      peak : int
          Sample where the peak under analysis is located.
      amp : int
          Amplitude of the peak under analysis.
      definitive_peaks : list
          List with the definitive_peaks stored until the present instant.
      spk1 : float
          Actual value of SPK1 parameter defined in Pan-Tompkins real-time R peak detection algorithm
          (named signal peak).
      rr_buffer : list
          Data structure that stores the duration of the last eight RR intervals.
  
      Returns
      -------
      definitive_peaks_out : list
          Definitive peaks list.
      spk1 : float
          Updated value of SPK1 parameter.
      rr_buffer : list
          Buffer after appending a new RR interval and excluding the oldest one.