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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 add_log_entry(self, process_name, timeperiod, msg):
 """ adds a non-persistent log entry to the tree node """

        tree = self.get_tree(process_name)
        node = tree.get_node(process_name, timeperiod)
        node.add_log_entry([datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S'), msg])