code: def _timeit_fast(stmt="pass", setup="pass", repeat=3):
      """
      Returns the time the statement/function took, in seconds.
  
      Faster, less precise version of IPython's timeit. `stmt` can be a statement
      written as a string or a callable.
  
      Will do only 1 loop (like IPython's timeit) with no repetitions
      (unlike IPython) for very slow functions.  For fast functions, only does
      enough loops to take 5 ms, which seems to produce similar results (on
      Windows at least), and avoids doing an extraneous cycle that isn't
      measured.
  
      """
      timer = timeit.Timer(stmt, setup)
  
      # determine number of calls per rep so total time for 1 rep >= 5 ms
      x = 0
      for p in range(0, 10):
          number = 10**p
          x = timer.timeit(number)  # seconds
          if (
              x >= 5e-3 / 10
          ):  # 5 ms for final test, 1/10th that for this one
              break
      if x > 1:  # second
          # If it's macroscopic, don't bother with repetitions
          best = x
      else:
          number *= 10
          r = timer.repeat(repeat, number)
          best = min(r)
  
      sec = best / number
      return sec
  
imports: import operator
  import math
  import timeit
  from scipy.spatial import cKDTree
  from .None import sigtools, dlti
  from ._upfirdn import upfirdn, _output_len, _upfirdn_modes
  from scipy import linalg, fft
  from scipy.fft._helper import _init_nd_shape_and_axes
  from scipy._lib._util import prod
  import numpy
  from scipy.special import lambertw
  from .windows import get_window
  from ._arraytools import axis_slice, axis_reverse, odd_ext, even_ext, const_ext
  from .filter_design import cheby1, _validate_sos
  from .fir_filter_design import firwin
  from ._sosfilt import _sosfilt
  import warnings
label_desc: Use image node_id 18 for calling a global function with example usage: _timeit_fast(stmt, setup, repeat) and returns: sec