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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 dropout(input_layer, keep_prob, phase=Phase.train, name=PROVIDED):
 """Aplies dropout if this is in the train phase."""

  if phase == Phase.train:
    return tf.nn.dropout(input_layer, keep_prob, name=name)
  else:
    return input_layer