I have been working on this for R Studio and I cant seem to get it right

## An open reading frame (ORF) is a stretch of sequence that starts with a start codon (ATG) ## and ends with a stop codon (TAG, TAA, TGA) without any other stop codons in between. ## By enumerating ORFs, we can create a list of candidate proteins encoded by this coronavirus. ## Write a function that will find all ORFs with at least 60 aa. ## Your function should output start and stop position of all such ORFs.