code: def _2861_2871_merge_pdf(content: bytes, coverpage: bytes):
      with fitz.Document(
          stream=coverpage, filetype="pdf"
      ) as coverpage_pdf:
          with fitz.Document(
              stream=content, filetype="pdf"
          ) as content_pdf:
              coverpage_pdf.insert_pdf(content_pdf)
              doc = coverpage_pdf.write()
              return doc
  
file_path: pymudf/tests/test_insertpdf.py
imports: import os
  import re
  import fitz
label_desc: Use image node_id 6 for calling a global function with example usage: _2861_2871_merge_pdf(content, coverpage) and returns: doc