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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 loss(loss_value):
 """Calculates aggregated mean loss."""

  total_loss = tf.Variable(0.0, False)
  loss_count = tf.Variable(0, False)
  total_loss_update = tf.assign_add(total_loss, loss_value)
  loss_count_update = tf.assign_add(loss_count, 1)
  loss_op = total_loss / tf.cast(loss_count, tf.float32)
  return [total_loss_update, loss_count_update], loss_op