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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 _set_labels(node, apiserver_url, labels):
    '''Replace labels dict by a new one'''
    # Prepare URL
    url = "{0}/api/v1/nodes/{1}".format(apiserver_url, node)
    # Prepare data
    data = [{"op": "replace", "path": "/metadata/labels", "value": labels}]
    # Make request
    ret = _kpatch(url, data)
    if ret.get("status") == 404:
        return "Node {0} doesn't exist".format(node)
    return ret