code: def tf2sos(b, a, pairing=None, *, analog=False):
      """
      Return second-order sections from transfer function representation
  
      Parameters
      ----------
      b : array_like
          Numerator polynomial coefficients.
      a : array_like
          Denominator polynomial coefficients.
      pairing : {None, 'nearest', 'keep_odd', 'minimal'}, optional
          The method to use to combine pairs of poles and zeros into sections.
          See `zpk2sos` for information and restrictions on `pairing` and
          `analog` arguments.
      analog : bool, optional
          If True, system is analog, otherwise discrete.
  
      Returns
      -------
      sos : ndarray
          Array of second-order filter coefficients, with shape
          ``(n_sections, 6)``. See `sosfilt` for the SOS filter format
          specification.
  
      See Also
      --------
      scipy.signal.tf2sos
  
      Notes
      -----
      It is generally discouraged to convert from TF to SOS format, since doing
      so usually will not improve numerical precision errors. Instead, consider
      designing filters in ZPK format and converting directly to SOS. TF is
      converted to SOS by first converting to ZPK format, then converting
      ZPK to SOS.
  
      """
      return zpk2sos(*tf2zpk(b, a), pairing=pairing, analog=analog)
  
imports: import warnings
  import math
  from math import pi, prod
  import cupy
  from cupyx.scipy.special import binom
  import cupyx.scipy.special
  from cupyx.scipy.signal import _optimize
  from cupyx.scipy.signal._polyutils import roots, poly
  from cupyx.scipy.signal._lti_conversion import abcd_normalize
label_desc: Use image node_id 22 for calling a global function with example usage: tf2sos(b, a, pairing) and returns: zpk2sos