code: def test_b16decode(self):
      eq = self.assertEqual
      eq(base64.b16decode(b"0102ABCDEF"), b"\x01\x02\xab\xcd\xef")
      eq(base64.b16decode("0102ABCDEF"), b"\x01\x02\xab\xcd\xef")
      eq(base64.b16decode(b"00"), b"\x00")
      eq(base64.b16decode("00"), b"\x00")
      # Lower case is not allowed without a flag
      self.assertRaises(binascii.Error, base64.b16decode, b"0102abcdef")
      self.assertRaises(binascii.Error, base64.b16decode, "0102abcdef")
      # Case fold
      eq(base64.b16decode(b"0102abcdef", True), b"\x01\x02\xab\xcd\xef")
      eq(base64.b16decode("0102abcdef", True), b"\x01\x02\xab\xcd\xef")
      # Non-bytes
      self.check_other_types(
          base64.b16decode, b"0102ABCDEF", b"\x01\x02\xab\xcd\xef"
      )
      self.check_decode_type_errors(base64.b16decode)
      eq(
          base64.b16decode(bytearray(b"0102abcdef"), True),
          b"\x01\x02\xab\xcd\xef",
      )
      eq(
          base64.b16decode(memoryview(b"0102abcdef"), True),
          b"\x01\x02\xab\xcd\xef",
      )
      eq(
          base64.b16decode(array("B", b"0102abcdef"), True),
          b"\x01\x02\xab\xcd\xef",
      )
      # Non-alphabet characters
      self.assertRaises(binascii.Error, base64.b16decode, "0102AG")
      # Incorrect "padding"
      self.assertRaises(binascii.Error, base64.b16decode, "010")
  
imports: import unittest
  import base64
  import binascii
  import os
  from array import array
  from test.support import os_helper
  from test.support import script_helper
label_desc: Use image node_id 20 for calling the BaseXYTestCase obj's underlying member method code with example usage: obj.test_b16decode() without return types