def remark_docstyle(source_files, docstyle_checks_total, ignored_pydocstyle_files, display_results):
    """Generate remark when not all source files are checked by pydocstyle."""
    if not display_results:
        return "<li>docstyle checker is not setup</li>"
    elif source_files != docstyle_checks_total + ignored_pydocstyle_files:
        return "<li>not all source files are checked by pydocstyle</li>"
    return ""