i have developed a custom field that extends ImageField and this custom field, dynamically creates 2more normal fields. Now, I need to write tests for this custom fields ? 
What tests are needed for this customfield ? Can you name them so that I will code those test cases. I am not asking technically how to write a test, I donno but I wil learn . But, what I want to know is, what are the things I need to test here.
Try to test every case of how your custom field could be used. In example try to send by it different kind of datas (string, integers, blank, different image formats etc.) and check if it works according to your expectations.
What tests do I need to write for the customfield that I have developed?