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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 contents(self, path):
 """ Reads the given path of current ref_head and returns its content as utf-8 """

        try:
            out, code, err = self.command_exec(['cat-file', '-p', self.ref_head+':'+path])
            if not code:
                return out.decode('utf-8')
        except Exception:
            pass

        return None