public function withCertificates(Certificate ...$cert): self
    {
        $obj = clone $this;
        $obj->_certs = array_merge($obj->_certs, $cert);
        return $obj;
    }
public function withCertificates(Certificate ...$cert): self
    {
        $obj = clone $this;
        $obj->_certs = array_merge($obj->_certs, $cert);
        return $obj;
    }
public function withCertificates ( Certificate ... $ cert ) : self { $ obj = clone $ this ; $ obj -> _certs = array_merge ( $ obj -> _certs , $ cert ) ; return $ obj ; }
Get self with certificates added.

@param Certificate ...$cert
@return self
Get self with certificates added .