def parse_field_children(self, messageSchema, parent: FieldCollection, element):
    'parse child elements that fit in a fieldCollection'
    for child_element in element:
        if (child_element.tag not in self.VALID_MESSAGE_TYPES):
            raise ValueError(f'invalid message/group child element {repr(child_element.tag)}')
        parser = getattr(self, f'parse_message_{child_element.tag}', None)
        if (not parser):
            raise RuntimeError(f'unsupported message parser {repr(child_element.tag)}')
        parser(messageSchema, parent, child_element)
parse child elements that fit in a fieldCollection
def parse_field_children(self, messageSchema, parent: FieldCollection, element):
    
    for child_element in element:
        if (child_element.tag not in self.VALID_MESSAGE_TYPES):
            raise ValueError(f'invalid message/group child element {repr(child_element.tag)}')
        parser = getattr(self, f'parse_message_{child_element.tag}', None)
        if (not parser):
            raise RuntimeError(f'unsupported message parser {repr(child_element.tag)}')
        parser(messageSchema, parent, child_element)