class_docstr: Builder that outputs epub files.
  
  It creates the metainfo files container.opf, toc.ncx, mimetype, and
  META-INF/container.xml.  Afterwards, all necessary files are zipped to an
  epub file.
class_docstr_tok: ["Builder","that","outputs","epub","files",".","It","creates","the","metainfo","files","container.opf",",","toc.ncx",",","mimetype",",","and","META-INF\/container.xml",".","Afterwards",",","all","necessary","files","are","zipped","to","an","epub","file","."]
docstr: Write one document file.
  
  This method is overwritten in order to fix fragment identifiers
  and to add visible external links.
code: def write_doc(self, docname: str, doctree: nodes.document) -> None:
      """Write one document file.
  
      This method is overwritten in order to fix fragment identifiers
      and to add visible external links.
      """
      self.fix_ids(doctree)
      self.add_visible_links(doctree, self.config.epub_show_urls)
      super().write_doc(docname, doctree)
  
imports: from __future__ import annotations
  import html
  import os
  import re
  import time
  from os import path
  from typing import TYPE_CHECKING, Any, NamedTuple
  from urllib.parse import quote
  from zipfile import ZIP_DEFLATED, ZIP_STORED, ZipFile
  from docutils import nodes
  from docutils.utils import smartquotes
  from sphinx import addnodes
  from sphinx.builders.html import BuildInfo, StandaloneHTMLBuilder
  from sphinx.locale import __
  from sphinx.util import logging
  from sphinx.util.display import status_iterator
  from sphinx.util.fileutil import copy_asset_file
  from sphinx.util.osutil import copyfile, ensuredir, relpath
label_desc: Use image node_id 12 for calling the EpubBuilder obj's underlying member method code with example usage: obj.write_doc(docname, doctree) without return types