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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 get_attribute_at(config, target_path, key, default_value=None):
 """ Return attribute value at a given path :param config: :param target_path: :param key: :param default_value: :return: """

    for target in target_path:
        config = config[target]
    return config[key] if key in config else default_value