I have written a custom google apps script function that is being called by a google sheet. In this function an API is called and the result of this API is being returned so that it gets displayed in the calling cell of the google sheet.
My problem now is that the sheet calls this function everytime I open the document and there are over 80.000 cells with this function.
Is it possible to save the returned value to the cell and don't call the custom function again when an value has been returned? I want the function being called only once per cell, even if I close the document and reopen it. The returned value should be saved until something else is being written into to cell. That would make my sheets document much more usable than the current state.