code: def write_svg_depth(filename: str, depth: int) -> None:
      """Write the depth to SVG file as a comment at end of file"""
      with open(filename, "a", encoding="utf-8") as f:
          f.write("\n<!-- DEPTH=%s -->" % depth)
  
imports: from __future__ import annotations
  import base64
  import contextlib
  import re
  import shutil
  import subprocess
  import tempfile
  from hashlib import sha1
  from os import path
  from subprocess import CalledProcessError
  from typing import TYPE_CHECKING, Any
  from docutils import nodes
  import sphinx
  from sphinx import package_dir
  from sphinx.errors import SphinxError
  from sphinx.locale import _, __
  from sphinx.util import logging
  from sphinx.util.math import get_node_equation_number, wrap_displaymath
  from sphinx.util.osutil import ensuredir
  from sphinx.util.png import read_png_depth, write_png_depth
  from sphinx.util.template import LaTeXRenderer
label_desc: Use image node_id 2 for calling a global function with example usage: write_svg_depth(filename, depth) without return types