text: import time
  
  def tic(verb=True):
      """ tic like Matlab function """
  
      global tic_toc_time
      tic_toc_time = time.time()
      if verb:
          print('start...')
      return tic_toc_time
  
  def toc(verb=True):
      """ toc like Matlab function """
  
      global tic_toc_time
      T1 = time.time()-tic_toc_time
      if verb:
          print('elapsed = ' + str(T1))
      return T1
  