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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 resources_of_config(config):
 """ Returns all resources and models from config. """

    return set(             # unique values
        sum([               # join lists to flat list
            list(value)     # if value is iter (ex: list of resources)
            if hasattr(value, '__iter__')
            else [value, ]  # if value is not iter (ex: model or resource)
            for value in config.values()
        ], [])
    )