<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def probe(filename, cmd='ffprobe', **kwargs):
 """Run ffprobe on the specified file and return a JSON representation of the output. Raises: :class:`ffmpeg.Error`: if ffprobe returns a non-zero exit code, an :class:`Error` is returned with a generic error message. The stderr output can be retrieved by accessing the ``stderr`` property of the exception. """

    args = [cmd, '-show_format', '-show_streams', '-of', 'json']
    args += convert_kwargs_to_cmd_line_args(kwargs)
    args += [filename]

    p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    out, err = p.communicate()
    if p.returncode != 0:
        raise Error('ffprobe', out, err)
    return json.loads(out.decode('utf-8'))