code: def iirpeak(w0, Q, fs=2.0):
      """
      Design second-order IIR peak (resonant) digital filter.
  
      A peak filter is a band-pass filter with a narrow bandwidth
      (high quality factor). It rejects components outside a narrow
      frequency band.
  
      Parameters
      ----------
      w0 : float
          Frequency to be retained in a signal. If `fs` is specified, this is in
          the same units as `fs`. By default, it is a normalized scalar that must
          satisfy  ``0 < w0 < 1``, with ``w0 = 1`` corresponding to half of the
          sampling frequency.
      Q : float
          Quality factor. Dimensionless parameter that characterizes
          peak filter -3 dB bandwidth ``bw`` relative to its center
          frequency, ``Q = w0/bw``.
      fs : float, optional
          The sampling frequency of the digital system.
  
  
      Returns
      -------
      b, a : ndarray, ndarray
          Numerator (``b``) and denominator (``a``) polynomials
          of the IIR filter.
  
      See Also
      --------
      scpy.signal.iirpeak
  
      References
      ----------
      Sophocles J. Orfanidis, "Introduction To Signal Processing",
         Prentice-Hall, 1996
      """
  
      return _design_notch_peak_filter(w0, Q, "peak", fs)
  
file_path: cupy/cupyx/scipy/signal/_iir_filter_design.py
imports: from math import pi
  import math
  import cupy
  from cupyx.scipy.signal._iir_filter_conversions import lp2bp_zpk, lp2lp_zpk, lp2hp_zpk, lp2bs_zpk, bilinear_zpk, zpk2tf, zpk2sos
  from cupyx.scipy.signal._iir_filter_conversions import buttap, cheb1ap, cheb2ap, ellipap, buttord, ellipord, cheb1ord, cheb2ord, _validate_gpass_gstop
label_desc: Use image node_id 10 for calling a global function with example usage: iirpeak(w0, Q, fs) and returns: _design_notch_peak_filter