def getChildren(self, returned_properties=None):
        """Get all the children workitems of this workitem

        If no children, None will be returned.

        :param returned_properties: the returned properties that you want.
            Refer to :class:`rtcclient.client.RTCClient` for more explanations
        :return: a :class:`rtcclient.workitem.Workitem` object
        :rtype: rtcclient.workitem.Workitem
        """

        children_tag = ("rtc_cm:com.ibm.team.workitem.linktype."
                        "parentworkitem.children")
        rp = returned_properties
        return (self.rtc_obj
                    ._get_paged_resources("Children",
                                          workitem_id=self.identifier,
                                          customized_attr=children_tag,
                                          page_size="10",
                                          returned_properties=rp))
Get all the children workitems of this workitem

        If no children, None will be returned.

        :param returned_properties: the returned properties that you want.
            Refer to :class:`rtcclient.client.RTCClient` for more explanations
        :return: a :class:`rtcclient.workitem.Workitem` object
        :rtype: rtcclient.workitem.Workitem