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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def html_page_context(cls, app, pagename, templatename, context, doctree):
 """Update the Jinja2 HTML context, exposes the Versions class instance to it. :param sphinx.application.Sphinx app: Sphinx application object. :param str pagename: Name of the page being rendered (without .html or any file extension). :param str templatename: Page name with .html. :param dict context: Jinja2 HTML context. :param docutils.nodes.document doctree: Tree of docutils nodes. """

        assert templatename or doctree  # Unused, for linting.
        cls.VERSIONS.context = context
        versions = cls.VERSIONS
        this_remote = versions[cls.CURRENT_VERSION]
        banner_main_remote = versions[cls.BANNER_MAIN_VERSION] if cls.SHOW_BANNER else None

        # Update Jinja2 context.
        context['bitbucket_version'] = cls.CURRENT_VERSION
        context['current_version'] = cls.CURRENT_VERSION
        context['github_version'] = cls.CURRENT_VERSION
        context['html_theme'] = app.config.html_theme
        context['scv_banner_greatest_tag'] = cls.BANNER_GREATEST_TAG
        context['scv_banner_main_ref_is_branch'] = banner_main_remote['kind'] == 'heads' if cls.SHOW_BANNER else None
        context['scv_banner_main_ref_is_tag'] = banner_main_remote['kind'] == 'tags' if cls.SHOW_BANNER else None
        context['scv_banner_main_version'] = banner_main_remote['name'] if cls.SHOW_BANNER else None
        context['scv_banner_recent_tag'] = cls.BANNER_RECENT_TAG
        context['scv_is_branch'] = this_remote['kind'] == 'heads'
        context['scv_is_greatest_tag'] = this_remote == versions.greatest_tag_remote
        context['scv_is_recent_branch'] = this_remote == versions.recent_branch_remote
        context['scv_is_recent_ref'] = this_remote == versions.recent_remote
        context['scv_is_recent_tag'] = this_remote == versions.recent_tag_remote
        context['scv_is_root'] = cls.IS_ROOT
        context['scv_is_tag'] = this_remote['kind'] == 'tags'
        context['scv_show_banner'] = cls.SHOW_BANNER
        context['versions'] = versions
        context['vhasdoc'] = versions.vhasdoc
        context['vpathto'] = versions.vpathto

        # Insert banner into body.
        if cls.SHOW_BANNER and 'body' in context:
            parsed = app.builder.templates.render('banner.html', context)
            context['body'] = parsed + context['body']
            # Handle overridden css_files.
            css_files = context.setdefault('css_files', list())
            if '_static/banner.css' not in css_files:
                css_files.append('_static/banner.css')
            # Handle overridden html_static_path.
            if STATIC_DIR not in app.config.html_static_path:
                app.config.html_static_path.append(STATIC_DIR)

        # Reset last_updated with file's mtime (will be last git commit authored date).
        if app.config.html_last_updated_fmt is not None:
            file_path = app.env.doc2path(pagename)
            if os.path.isfile(file_path):
                lufmt = app.config.html_last_updated_fmt or getattr(locale, '_')('%b %d, %Y')
                mtime = datetime.datetime.fromtimestamp(os.path.getmtime(file_path))
                context['last_updated'] = format_date(lufmt, mtime, language=app.config.language, warn=app.warn)