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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def compute_offset_to_first_complete_codon( offset_to_first_complete_reference_codon, n_trimmed_from_reference_sequence):
 """ Once we've aligned the variant sequence to the ReferenceContext, we need to transfer reading frame from the reference transcripts to the variant sequences. Parameters offset_to_first_complete_reference_codon : int n_trimmed_from_reference_sequence : int Returns an offset into the variant sequence that starts from a complete codon. """

    if n_trimmed_from_reference_sequence <= offset_to_first_complete_reference_codon:
        return (
            offset_to_first_complete_reference_codon -
            n_trimmed_from_reference_sequence)
    else:
        n_nucleotides_trimmed_after_first_codon = (
            n_trimmed_from_reference_sequence -
            offset_to_first_complete_reference_codon)
        frame = n_nucleotides_trimmed_after_first_codon % 3
        return (3 - frame) % 3