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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 _RetryLoop(self, func, timeout=None):
 """Retries an operation until success or deadline. Args: func: The function to run. Must take a timeout, in seconds, as a single parameter. If it raises grpc.RpcError and deadline has not be reached, it will be run again. timeout: Retries will continue until timeout seconds have passed. """

    timeout = timeout or self.DEFAULT_TIMEOUT
    deadline = time.time() + timeout
    sleep = 1
    while True:
      try:
        return func(timeout)
      except grpc.RpcError:
        if time.time() + sleep > deadline:
          raise
        time.sleep(sleep)
        sleep *= 2
        timeout = deadline - time.time()