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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _render_cmd(cmd, cwd, template, saltenv='base', pillarenv=None, pillar_override=None):
    '''
    If template is a valid template engine, process the cmd and cwd through
    that engine.
    '''
    if not template:
        return (cmd, cwd)

    # render the path as a template using path_template_engine as the engine
    if template not in salt.utils.templates.TEMPLATE_REGISTRY:
        raise CommandExecutionError(
            'Attempted to render file paths with unavailable engine '
            '{0}'.format(template)
        )

    kwargs = {}
    kwargs['salt'] = __salt__
    if pillarenv is not None or pillar_override is not None:
        pillarenv = pillarenv or __opts__['pillarenv']
        kwargs['pillar'] = _gather_pillar(pillarenv, pillar_override)
    else:
        kwargs['pillar'] = __pillar__
    kwargs['grains'] = __grains__
    kwargs['opts'] = __opts__
    kwargs['saltenv'] = saltenv

    def _render(contents):
        # write out path to temp file
        tmp_path_fn = salt.utils.files.mkstemp()
        with salt.utils.files.fopen(tmp_path_fn, 'w+') as fp_:
            fp_.write(salt.utils.stringutils.to_str(contents))
        data = salt.utils.templates.TEMPLATE_REGISTRY[template](
            tmp_path_fn,
            to_str=True,
            **kwargs
        )
        salt.utils.files.safe_rm(tmp_path_fn)
        if not data['result']:
            # Failed to render the template
            raise CommandExecutionError(
                'Failed to execute cmd with error: {0}'.format(
                    data['data']
                )
            )
        else:
            return data['data']

    cmd = _render(cmd)
    cwd = _render(cwd)
    return (cmd, cwd)