'Append a value to a sequence.
Args:
subject: _ObjectSequence that is receiving new value.
value: Value that is being appended to sequence.'

def AppendTo(self, subject, value):

    if isinstance(value, _ObjectMapper):
        value.set_value(subject.constructor())
        subject.value.append(value.value)
    else:
        subject.value.append(value)
