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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 uninstall(pkg):
    '''
    Uninstall the specified package.

    Args:
        pkg (str): The package name.

    Returns:
        dict: The ``result`` and ``output``.

    CLI Example:

    .. code-block:: bash

        salt '*' flatpak.uninstall org.gimp.GIMP
    '''
    ret = {'result': None, 'output': ''}

    out = __salt__['cmd.run_all'](FLATPAK_BINARY_NAME + ' uninstall ' + pkg)

    if out['retcode'] and out['stderr']:
        ret['stderr'] = out['stderr'].strip()
        ret['result'] = False
    else:
        ret['stdout'] = out['stdout'].strip()
        ret['result'] = True

    return ret