code: def copyWorkitem(self, copied_from, title=None, description=None,
                       prefix=None):
          
  
          copied_wi = self.getWorkitem(copied_from)
          if title is None:
              title = copied_wi.title
              if prefix is not None:
                  title = prefix + title
  
          if description is None:
              description = copied_wi.description
              if prefix is not None:
                  description = prefix + description
  
          self.log.info("Start to create a new <Workitem>, copied from ",
                        "<Workitem %s>", copied_from)
  
          wi_url_post = "/".join([self.url,
                                  "oslc/contexts/%s" % copied_wi.contextId,
                                  "workitems",
                                  "%s" % copied_wi.type.split("/")[-1]])
          wi_raw = self.templater.renderFromWorkitem(copied_from,
                                                     keep=True,
                                                     encoding="UTF-8",
                                                     title=title,
                                                     description=description)
          return self._createWorkitem(wi_url_post, wi_raw)
docs: Create a workitem by copying from an existing one
  
          :param copied_from: the to-be-copied workitem id
          :param title: the new workitem title/summary.
              If `None`, will copy that from a to-be-copied workitem
          :param description: the new workitem description.
              If `None`, will copy that from a to-be-copied workitem
          :param prefix: used to add a prefix to the copied title and
              description
          :return: the :class:`rtcclient.workitem.Workitem` object
          :rtype: rtcclient.workitem.Workitem