code: def format_time_small(seconds):
      
  
      if not isinstance(seconds, (int, float)):
          return str(seconds)
  
      if math.isnan(seconds):
          return "-"
  
      if abs(seconds)<1:
          milliseconds = 1000*seconds
          if abs(milliseconds)<1:
              microseconds = 1000*milliseconds
              if abs(microseconds)<1:
                  nanoseconds = 1000*microseconds
                  if abs(nanoseconds)<0.5:
                      return "0"
                  else:
                      return "{:.0f}ns".format(nanoseconds)
              elif abs(microseconds)<10:
                  return "{:.2f}us".format(microseconds)
              elif abs(microseconds)<100:
                  return "{:.1f}us".format(microseconds)
              else:
                  return "{:.0f}us".format(microseconds)
          elif abs(milliseconds)<10:
              return "{:.2f}ms".format(milliseconds)
          elif abs(milliseconds)<100:
              return "{:.1f}ms".format(milliseconds)
          else:
              return "{:.0f}ms".format(milliseconds)
      elif abs(seconds)<10:
              return "{:.2f}s".format(seconds)
      elif abs(seconds)<100:
          return "{:.1f}s".format(seconds)
      else:
          return "{:.0f}s".format(seconds)
docs: Same as format_time() but always uses SI-prefix and 3 significant figures.