APEX Rest with Mock Animal locator

AnimalLocator.apxc

public class AnimalLocator {
      
    public static String getAnimalNameById(Integer i){
         
        Http http = new Http();
        HttpRequest request = new HttpRequest();
        request.setEndpoint('https://th-apex-http-callout.herokuapp.com/animals/' + i);
        request.setMethod('GET');
        HttpResponse response = http.send(request);
        
        
        // If the request is successful, parse the JSON response.
        if(response.getStatusCode() == 200) {
            // Deserializes the JSON string into collections of primitive data types.
            Map<String, Object> result = (Map<String, Object>) JSON.deserializeUntyped(response.getBody());
            Map<String, Object> animal = (Map<String, Object>) result.get('animal');
            
            
            System.debug('Received the following animal name:');
            System.debug(string.valueOf(animal.get('name')));
            return string.valueOf(animal.get('name'));
            
        } 
        
        return null;    
        
        
        
    }

}

AnimalLocatorMock.aspxc

@isTest
global class AnimalLocatorMock implements HttpCalloutMock {
	// Implement this interface method
    global HTTPResponse respond(HTTPRequest request) {
        // Create a fake response
        HttpResponse response = new HttpResponse();
        response.setHeader('Content-Type', 'application/json');
        response.setBody('{"animal": {"id":1,"name": "moose", "eats":"plants","says":"bellows"}}');
        response.setStatusCode(200);
        return response; 
	}
}

AnimalLOcatorTest.aspx

@isTest
public class AnimalLocatorTest {
    
    @isTest static void testGetAnimalNameById() {
            Test.setMock(HttpCalloutMock.class, new AnimalLocatorMock());
        	String result = AnimalLocator.getAnimalNameById(1);
        	System.assertEquals('moose', result);
    }
    
    @isTest static void testGetAnimalNameById500() {
        	StaticResourceCalloutMock mock = new StaticResourceCalloutMock();
			mock.setStaticResource('GetAnimalResource');
        	// Set a failed request code - content can be ignored
        	mock.setStatusCode(500);
        	// Associate the callout with a mock response
        	Test.setMock(HttpCalloutMock.class, mock);
        
        	String result = AnimalLocator.getAnimalNameById(1);
        	System.assertEquals(null, result);
    }
    
    
}