code: def get_cgi_parameter_filename_and_file(form: cgi.FieldStorage, key: str) \
          -> Tuple[Optional[str], Optional[bytes]]:
      
      if not (key in form):
          log.warning('get_cgi_parameter_file: form has no key {}', key)
          return None, None
      fileitem = form[key]  # a nested FieldStorage instance; see
      # http://docs.python.org/2/library/cgi.html#using-the-cgi-module
      if isinstance(fileitem, cgi.MiniFieldStorage):
          log.warning('get_cgi_parameter_file: MiniFieldStorage found - did you '
                      'forget to set enctype="multipart/form-data" in '
                      'your form?')
          return None, None
      if not isinstance(fileitem, cgi.FieldStorage):
          log.warning('get_cgi_parameter_file: no FieldStorage instance with '
                      'key {} found', key)
          return None, None
      if fileitem.filename and fileitem.file:  # can check "file" or "filename"
          return fileitem.filename, fileitem.file.read()
          # as per
          # http://upsilon.cc/~zack/teaching/0607/techweb/02-python-cgi.pdf
          # Alternative:
          # return get_cgi_parameter_str(form, key) # contents of the file
      # Otherwise, information about problems:
      if not fileitem.file:
          log.warning('get_cgi_parameter_file: fileitem has no file')
      elif not fileitem.filename:
          log.warning('get_cgi_parameter_file: fileitem has no filename')
      else:
          log.warning('get_cgi_parameter_file: unknown failure reason')
      return None, None
docs: Extracts a file's name and contents from a "file" input in a CGI form.
      Returns ``(name, contents)``, or ``(None, None)`` if no such file was
      uploaded.