code: def removeParent(self):
          
  
          self.log.debug("Try to remove the parent workitem from current "
                         "<Workitem %s>",
                         self)
  
          headers = copy.deepcopy(self.rtc_obj.headers)
          headers["Content-Type"] = self.OSLC_CR_JSON
          req_url = "".join([self.url,
                             "?oslc_cm.properties=com.ibm.team.workitem.",
                             "linktype.parentworkitem.parent"])
  
          parent_tag = ("rtc_cm:com.ibm.team.workitem.linktype."
                        "parentworkitem.parent")
          parent_original = {parent_tag: []}
  
          self.put(req_url,
                   verify=False,
                   proxies=self.rtc_obj.proxies,
                   headers=headers,
                   data=json.dumps(parent_original))
          self.log.info("Successfully remove the parent workitem of current "
                        "<Workitem %s>",
                        self)
docs: Remove the parent workitem from current workitem
  
          Notice: for a certain workitem, no more than one parent workitem
          can be added and specified