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The extend execution
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Would you please tell me why predecessors the extend will carry out the "lee" into three elements,,,
To solve, thank you!
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CodePudding user response:
Append and extend are at the end of the list add elements;Add elements, are the way of the container to add;
The difference is that although both is added in the form of the container, but append add do add the container as a whole, but the extend is broken after adding the container just elements (join)