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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 Backtrace(self, to_string=False):
 """Get a backtrace of the current position."""

    if self.inferior.is_running:
      res = self.inferior.Backtrace()
      if to_string:
        return res
      print res
    else:
      logging.error('Not attached to any process.')