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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 name_insertion(sbjct_seq, codon_no, sbjct_nucs, aa_alt, start_offset):
 """ This function is used to name a insertion mutation based on the HGVS recommendation. """

    start_codon_no = codon_no - 1
    if len(sbjct_nucs) == 3:
        start_codon_no = codon_no
    start_codon = get_codon(sbjct_seq, start_codon_no, start_offset)
    end_codon = get_codon(sbjct_seq, codon_no, start_offset)
    pos_name = "p.%s%d_%s%dins%s"%(aa(start_codon), start_codon_no, aa(end_codon), codon_no, aa_alt)
    return pos_name