code: def besselap():
      raise NotImplementedError
  
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 1 for calling a global function with example usage: besselap() without return types