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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 _set_def_prompt(self):
 """Sets the default prompt to match the currently active unit test."""

        if len(self.active) > 15:
            ids = self.active.split(".")
            if len(ids) > 2:
                module, executable, compiler = ids
            else:
                module, executable = ids
                compiler = "g"
            self.prompt = "({}*.{}*.{}:{})".format(module[0:6], executable[0:6], compiler, self.group)
        else:
            self.prompt = "({}:{})".format(self.active, self.group)