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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 _format_device(var):
 """Returns the device with an annotation specifying `ResourceVariable`. "legacy" means a normal tf.Variable while "resource" means a ResourceVariable. For example: `(legacy)` `(resource)` `/job:learner/task:0/device:CPU:* (legacy)` `/job:learner/task:0/device:CPU:* (resource)` Args: var: The Tensorflow Variable to print. """

  if var.dtype.name.endswith("_ref"):
    resource_var_annotation = "(legacy)"
  else:
    resource_var_annotation = "(resource)"

  if var.device:
    return "{} {}".format(var.device, resource_var_annotation)
  else:
    return resource_var_annotation