def METHOD_NAME(self):
    key1_string = 'AWS4' + 'S3CR3T'
    key1 = key1_string.encode('utf-8')
    key2 = hmac.new(key1, '20150620'.encode(
        'utf-8'), hashlib.sha256).digest()
    key3 = hmac.new(key2, 'region'.encode(
        'utf-8'), hashlib.sha256).digest()
    key4 = hmac.new(key3, 's3'.encode('utf-8'), hashlib.sha256).digest()
    expected_result = hmac.new(key4, 'aws4_request'.encode(
        'utf-8'), hashlib.sha256).digest()
    actual_result = _get_signing_key('S3CR3T', dt, 'region', "s3")
    self.assertEqual(expected_result, actual_result)