def nt_pos_shift(nt_pos, AAshift):
    """
		Modify nucleotide positions in our alignment to actual positions in the real wild-type sequence.

		nt_pos : base number of wild type sequence start at 1, not python 0
		AAshift : the residue corresponding to the wild type base starting at 1
	"""
    if nt_pos < 1:
        raise Exception('Bases provided must start at 1')
    return nt_pos + (AAshift - 1) * 3
