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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 addChild(self, child_id):
 """Add a child to current workitem :param child_id: the child workitem id/number (integer or equivalent string) """


        self.log.debug("Try to add a child <Workitem %s> to current "
                       "<Workitem %s>",
                       child_id,
                       self)
        self._addChildren([child_id])
        self.log.info("Successfully add a child <Workitem %s> to current "
                      "<Workitem %s>",
                      child_id,
                      self)