code: def fir_remez_lpf(f_pass, f_stop, d_pass, d_stop, fs = 1.0, N_bump=5):
      
      n, ff, aa, wts = lowpass_order(f_pass, f_stop, d_pass, d_stop, fsamp=fs)
      # Bump up the order by N_bump to bring down the final d_pass & d_stop
      N_taps = n
      N_taps += N_bump
      b = signal.remez(N_taps, ff, aa[0::2], wts,Hz=2)
      print('Remez filter taps = %d.' % N_taps)
      return b
docs: Design an FIR lowpass filter using remez with order
      determination. The filter order is determined based on 
      f_pass Hz, fstop Hz, and the desired passband ripple 
      d_pass dB and stopband attenuation d_stop dB all 
      relative to a sampling rate of fs Hz.
  
      Mark Wickert October 2016, updated October 2018