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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 post(node_name, key, **kwargs):
 """ Give the server information about this node Arguments: node -- node_name or token for the node this data belongs to key -- identifiable key, that you use later to retrieve that piece of data kwargs -- the data you need to store """

    node = nago.core.get_node(node_name)
    if not node:
        raise ValueError("Node named %s not found" % node_name)
    token = node.token
    node_data[token] = node_data[token] or {}
    node_data[token][key] = kwargs
    return "thanks!"