files = None
try:
    self.parse_url_query(kwargs.get("query"))
    files = utils.read_files_for_upload(file)
    r = req.post(self.url, headers=headers, files=files, timeout=30)  # Added timeout
    r.raise_for_status()

    # Always ensure files are closed
    if files:
        utils.close_files_after_upload(files)

    try:
        return r.json()
    except req.exceptions.JSONDecodeError:
        # Handle special case where response contains multiple lines
        temp = r.text.split("\n")
        return json.loads(temp[-2])  # Use -2 index instead of len(temp) - 2
except Exception as e:
    # Ensure files are closed even if an error occurs
    if files:
        utils.close_files_after_upload(files)
    raise RequestException(f"File upload failed: {str(e)}")

try:
    for file in files["files"]:
        if not os.path.exists(file):
            raise ValueError(f"File does not exist: {file}")

        name = (extract_file_name_with_source(file, files["path"]) 
               if files["is_dir"] 
               else extract_file_name(file))

        file_list.append(
            (
                "file",
                (
                    name,
                    open(file, "rb"),
                    "application/octet-stream",
                ),
            )
        )
    return file_list

if not isinstance(source, io.BufferedReader):
    raise TypeError("source must be an instance of io.BufferedReader")

if not filename or not isinstance(filename, str):
    raise ValueError("filename must be a non-empty string")

if not (hasattr(source, 'read') and hasattr(source, 'close')):
    raise TypeError("source must have 'read' and 'close' methods")