code: public function setPassword($pp, $pca, $passwd)
      {
          if (!$pp)
              throw new BadMethodCallException('Missing parameter $pp (OVH cloud passport).');
          if (!$pca)
              throw new BadMethodCallException('Missing parameter $pca (PCA ServiceName).');
          if (!$passwd)
              throw new BadMethodCallException('Missing parameter $passwd (Password for this pca).');
          $payload = array('password' => $passwd);
          try {
              $this->put('cloud/' . $pp . '/pca/' . $pca, array('Content-Type' => 'application/json;charset=UTF-8'), json_encode($payload))->send();
          } catch (\Exception $e) {
              throw new CloudException($e->getMessage(), $e->getCode(), $e);
          }
      }
docs: Set password to PCA
  
  @param string $pp OVH cloud passport
  @param string $pca PCA service name
  @param string $passwd
  @throws \Ovh\Cloud\Exception\CloudException
  @throws \Ovh\Common\Exception\BadMethodCallException