How to split input data to train & test set

Hi;

Is there any functionexist to divide data into train_data & test_data

I have below data:Currently I do it manually,

I want to divide the data in to 70% (train data) and 30% test data. and how to overcome fraction(suppose if data size 11, 70%-->7.7, in this kind of situation take nearest roundoff whole number i.e., 8, test data is 3)

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