code: def get_mupdf_tgz():
      """
      Creates .tgz file called containing MuPDF source, for inclusion in an
      sdist.
  
      What we do depends on environmental variable PYMUPDF_SETUP_MUPDF_TGZ; see
      docs at start of this file for details.
  
      Returns name of top-level directory within the .tgz file.
      """
      name = get_mupdf_internal(
          "tgz", os.environ.get("PYMUPDF_SETUP_MUPDF_TGZ")
      )
      return name
  
imports: import glob
  import io
  import os
  import textwrap
  import time
  import platform
  import shlex
  import shutil
  import stat
  import subprocess
  import sys
  import tarfile
  import urllib.request
  import zipfile
  import pipcl
  import sys
label_desc: Use image node_id 9 for calling a global function with example usage: get_mupdf_tgz() and returns: name