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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 dump(node, config):
 """ Convert a node tree to a simple nested dict All steps in this conversion are configurable using DumpConfig dump dictionary node: {"type": str, "data": dict} """

    if config.is_node(node):
        fields = OrderedDict()
        for name in config.fields_iter(node):
            attr = config.field_val(node, name)
            if attr is not None:
                fields[name] = dump(attr, config)
        return {"type": config.node_type(node), "data": fields}
    elif config.is_list(node):
        return [dump(x, config) for x in config.list_iter(node)]
    else:
        return config.leaf_val(node)