Clarify the random_state description in train_test_split documentation

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Introduce yourself

No response

Describe the issue linked to the documentation

The random_state parameter in train_test_split could use a slightly clearer explanation for beginners.

It would be helpful to explicitly mention that using the same integer value produces the same split across repeated calls, assuming the same input data and parameters.

Suggest a potential alternative/fix

Add a short sentence to the random_state parameter documentation explaining that a fixed integer makes the split reproducible.