code: def _hs(k, cs, rho, omega):
      c0 = (
          cs
          * cs
          * (1 + rho * rho)
          / (1 - rho * rho)
          / (1 - 2 * rho * rho * cupy.cos(2 * omega) + rho**4)
      )
      gamma = (1 - rho * rho) / (1 + rho * rho) / cupy.tan(omega)
      ak = cupy.abs(k)
      return (
          c0
          * rho**ak
          * (cupy.cos(omega * ak) + gamma * cupy.sin(omega * ak))
      )
  
imports: import cupy
  import cupyx.scipy.ndimage
  from cupyx.scipy.signal._iir_utils import apply_iir_sos
  from cupyx.scipy.signal._splines import _symiirorder1_nd, _symiirorder2_nd
  from cupyx.scipy.interpolate._bspline import BSpline
  import numpy
label_desc: Use image node_id 6 for calling a global function with example usage: _hs(k, cs, rho, omega) and returns: unknown