def METHOD_NAME(self):
    """Expand alphabet values for ambiguous codes."""
    self.alphabet = ambiguous_dna_values
    other = "".join(self.alphabet)
    self.alphabet["N"] = self.alphabet["N"] + other
    for key in self.alphabet:
        if key == "N":
            continue
        if key in self.alphabet[key]:
            continue
        self.alphabet[key] = self.alphabet[key] + key