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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 list():
    '''
    Get a list of updates installed on the machine

    Returns:
        list: A list of installed updates

    CLI Example:

    .. code-block:: bash

        salt '*' wusa.list
    '''
    kbs = []
    ret = _pshell_json('Get-HotFix | Select HotFixID')
    for item in ret:
        kbs.append(item['HotFixID'])
    return kbs