this is the code i've managed to write till now... no output though... 😞 can anyone guide me please!
	 
	 
	$signature = "xxxxx";
	$user_id = "xxxx";
	$encryption_key = "";
	if (isset($user_id) && isset($encryption_key)) { // execute only if both are set
	    $request_time = date(DATE_W3C, time());
	    $access_key = trim($user_id);
	    $secret_key = trim($encryption_key);
	    $encrypt_input = $request_time . $access_key;
	    $signature = hash_hmac('sha1', $encrypt_input, $secret_key);
	} else {
	    $user_id = '';
	    $encryption_key = '';
	}
	 
	 
	 
	//$client = new SoapClient(null);
	$attrs = array(
	    'mktowsUserId' => $access_key,
	    'requestSignature' => $signature,
	    'requestTimestamp' => $request_time,
	);
	 
	$client = new SoapClient("http://090-BZJ-603.mktoapi.com/soap/mktows/1_2?WSDL");
	$header = new SoapHeader('http://www.marketo.com/mktows/', 'AuthenticationHeader', $attrs);
	$client->__setSoapHeaders($header);
	 
	$xml = '<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:mkt="http://www.marketo.com/mktows/">
	   <soapenv:Header>
	      <mkt:AuthenticationHeader>
	         <mktowsUserId>'.$access_key.'</mktowsUserId>
	         <requestSignature>'.$signature.'</requestSignature>
	         <requestTimestamp>'.$request_time.'</requestTimestamp>
	        
	      </mkt:AuthenticationHeader>
	   </soapenv:Header>
	   <soapenv:Body>
	      <mkt:paramsGetMultipleLeads>
	        
	      </mkt:paramsGetMultipleLeads>
	   </soapenv:Body>
	</soapenv:Envelope>';
	 
	 
	print_r($client->__call("getMultipleLeads",$xml));