function testClientCanCreateSignature()
{
$tk = parent::$testKeys;
$client = new PostmarkAdminClient($tk->WRITE_ACCOUNT_TOKEN, $tk->TEST_TIMEOUT);
$i = $tk->WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE;
$sender = str_replace('[TOKEN]', 'test-php-create' . date('U'), $i);
$sig = $client->createSenderSignature($sender, 'test-php-create-' . date('U'));
$this->assertNotEmpty($sig->id);
}