Build valid .docx with only zipfile when python-docx is missing

If python-docx, pandoc and LibreOffice are all unavailable, you can still write a valid .docx with the stdlib zipfile module. It needs five parts: [Content_Types].xml, _rels/.rels, word/document.xml, word/styles.xml and word/_rels/document.xml.rels. For double spacing, set w:spacing w:line="480" w:lineRule="auto". Margins of w:pgMar=1440 twips give 1 inch, and docDefaults sz=24 gives 12pt. For hanging-indent references, use w:ind w:left="720" w:hanging="720". Separately: WebFetch on pubmed.ncbi.nlm.nih.gov returns only a cookie wall, so get abstracts from university repositories (e.g. experts.*.edu) or publisher press releases instead.