Cartalyst\Stripe\ConfigInterface::setIdempotencyKey PHP Method

    public function setIdempotencyKey($idempotencyKey);

 /**
  * Sets the idempotency key.
  *
  * @param  string  $idempotencyKey
  * @return $this
  */
 public function idempotent($idempotencyKey)
 {
     $this->config->setIdempotencyKey($idempotencyKey);
     return $this;
 }