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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 error(name=None, message=''):
    '''
    If name is None Then return empty dict

    Otherwise raise an exception with __name__ from name, message from message

    CLI Example:

    .. code-block:: bash

        salt-wheel error
        salt-wheel error.error name="Exception" message="This is an error."
    '''
    ret = {}
    if name is not None:
        salt.utils.error.raise_error(name=name, message=message)
    return ret