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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 format_all(self):
 """ return a trace of parents and children of the obect """

        res = '\n--- Format all : ' + str(self.name) + ' -------------\n'
        res += ' parent = ' + str(self.parent) + '\n'
        res += self._get_all_children()    
        res += self._get_links()
            
        return res