code: def transformFromNative(obj):
          
          if obj.value and type(obj.value[0]) == datetime.date:
              obj.isNative = False
              obj.value_param = 'DATE'
              obj.value = ','.join([dateToString(val) for val in obj.value])
              return obj
          # Fixme: handle PERIOD case
          else:
              if obj.isNative:
                  obj.isNative = False
                  transformed = []
                  tzid = None
                  for val in obj.value:
                      if tzid is None and type(val) == datetime.datetime:
                          tzid = TimezoneComponent.registerTzinfo(val.tzinfo)
                          if tzid is not None:
                              obj.tzid_param = tzid
                      transformed.append(dateTimeToString(val))
                  obj.value = ','.join(transformed)
              return obj
docs: Replace the date, datetime or period tuples in obj.value with
          appropriate strings.