liquibase-core/src/main/java/liquibase/Scope.java
public <T> T get(String key, Class<T> type) {
        T value = values.get(key, type);
        if (value == null && parent != null) {
            value = parent.get(key, type);
        }
        return value;
    }
public <T> T get(String key, Class<T> type) {
        T value = values.get(key, type);
        if (value == null && parent != null) {
            value = parent.get(key, type);
        }
        return value;
    }
Return the value associated with the given key in this scope or any parent scope.
The value is converted to the given type if necessary using {@link liquibase.util.ObjectUtil#convert(Object, Class)}.
Returns null if key is not defined in this or any parent scopes.