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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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))