Can a class be referenced to a label in html?

<label for="file_upload" class="custom-file_upload z-depth-1">
  <i class="material-icons">&#xE147;</i>
  <p class="button-text"> Upload Here</p>
</label>
  <input class="file_upload" type="file" accept="image/*" name="user_id" />

Is it possible to assign the for="file_upload" to the ID id="file_upload" in Input instead of class="file_upload"

When I tried it is not working for ID but it works for Class. May I know if I have to use some different approach to use class?