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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 find_root(self):

 """Find a function without a caller"""

        self.profdata.sort_stats("cumulative")
        for func in self.profdata.fcn_list:
            if ('~', 0) != func[0:2] and not func[2].startswith(
                    '<built-in method exec>'):
                # This skips the profiler function at the top of the list
                # it does only occur in Python 3
                return func