code: def wfdb_strptime(time_string):
      
      n_colons = time_string.count(':')
  
      if n_colons == 0:
          time_fmt = '%S'
      elif n_colons == 1:
          time_fmt = '%M:%S'
      elif n_colons == 2:
          time_fmt = '%H:%M:%S'
  
      if '.' in time_string:
          time_fmt += '.%f'
  
      return datetime.datetime.strptime(time_string, time_fmt).time()
docs: Given a time string in an acceptable wfdb format, return
      a datetime.time object.
  
      Valid formats: SS, MM:SS, HH:MM:SS, all with and without microsec.