code: public boolean hasSlotIsCologneEqual(final String slotName, final String value) {
          final String slotValue = getSlotValue(slotName);
          return hasSlotNotBlank(slotName) && value != null &&
                  new ColognePhonetic().isEncodeEqual(slotValue, value);
      }
docs: Checks if a slot is contained in the intent request and has a value which is a
  phonetic sibling of the string given to this method. Cologne phonetic algorithm
  is optimized for German language and in this case is used to match slot value with
  value given to this method.
  @param slotName name of the slot to look after
  @param value the value
  @return True, if slot value and given value are phonetically equal with Cologne phonetic algorithm