code: def test_sub_second(self):
      dt = datetime(2013, 1, 1, 0, 0, 0, 123456)
      assert self.formatter._format_token(dt, "SSSSSS") == "123456"
      assert self.formatter._format_token(dt, "SSSSS") == "12345"
      assert self.formatter._format_token(dt, "SSSS") == "1234"
      assert self.formatter._format_token(dt, "SSS") == "123"
      assert self.formatter._format_token(dt, "SS") == "12"
      assert self.formatter._format_token(dt, "S") == "1"
  
      dt = datetime(2013, 1, 1, 0, 0, 0, 2000)
      assert self.formatter._format_token(dt, "SSSSSS") == "002000"
      assert self.formatter._format_token(dt, "SSSSS") == "00200"
      assert self.formatter._format_token(dt, "SSSS") == "0020"
      assert self.formatter._format_token(dt, "SSS") == "002"
      assert self.formatter._format_token(dt, "SS") == "00"
      assert self.formatter._format_token(dt, "S") == "0"
  
imports: from datetime import datetime
  import pytest
  import pytz
  from dateutil import tz
  from arrow import FORMAT_ATOM, FORMAT_COOKIE, FORMAT_RFC822, FORMAT_RFC850, FORMAT_RFC1036, FORMAT_RFC1123, FORMAT_RFC2822, FORMAT_RFC3339, FORMAT_RSS, FORMAT_W3C
  from .utils import make_full_tz_list
label_desc: Use image node_id 8 for calling the TestFormatterFormatToken obj's underlying member method code with example usage: obj.test_sub_second() without return types