How we can import the line items in parent-child using excel

Summary: How we can import the line items in parent-child like 1.0, 1.1, 1.2, 1.3... then 2.0, 2.1,2.2, 2.3... and so on using excel

1.0 will me model and 1.1, 1.2 so on will be products

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