'Return a list of translations for an expression into a single language
variety.
:param from_uid: the source expression\'s language variety, as a
seven-character uniform identifier.
:param from_tt: the source expression\'s text.
:param to_uid: the target language variety, as a seven-character
uniform identifier.
:return a list of translation tuples. The first element is the expression
text and the second element is the translation quality.
:rtype: list(tuple)'

def translations(self, from_uid, from_tt, to_uid):

    from_lv = self._uid_lv[from_uid]
    to_lv = self._uid_lv[to_uid]
    return self._c.execute(self.TRANSLATION_Q, (from_lv, from_tt, to_lv)).fetchall()
