def pick_coda_from_letter(letter):
try:<EOL><INDENT>__, __, coda =split_phonemes(letter, onset=False, nucleus=False, coda=True)<EOL><DEDENT>except ValueError:<EOL><INDENT>return None<EOL><DEDENT>else:<EOL><INDENT>return coda<EOL><DEDENT>
Picks only a coda from a Hangul letter.  It returns ``None`` if the
    given letter is not Hangul.