InvalidIndexError: You can only assign a scalar value not a <class 'pandas.core.series.Series'>

Question

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Hello

I am trying to press the spx with a sarimas model, however i have not been able to solve this error, i would be grateful if you could give me guidance.

InvalidIndexError: You can only assign a scalar value not a <class 'pandas.core.series.Series'>

Notebook

I need this code segment to cover the process of making time series predictions, handling the transformations applied to the data, and managing the in-sample and out-of-sample predictions along with their confidence intervals.