title: Did you forget to register or load this tag? Django
body: <p><img src="https://i.stack.imgur.com/MIVSy.png" alt="enter image description here"></p>
  
  <blockquote>
    <p>Did you forget to register or load this tag? </p>
  </blockquote>
  
  <p>I was watching the django tutorial in udemy, and I follow the same step as the professor did. The error came out with the following error:</p>
  
  <blockquote>
    <p>Invalid block tag on line 9: "url"app4:other". Did you forget to register or load this tag?</p>
  </blockquote>