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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 create_weight_initializer(fan_in_shape, dtype=tf.float32):
 """Returns a default initializer for the weights of a convolutional module."""

  stddev = 1 / math.sqrt(np.prod(fan_in_shape))
  return tf.truncated_normal_initializer(stddev=stddev, dtype=dtype)