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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 normalize_std_array(vector):
 """Applies a unit mean and variance normalization to an arrayset"""


  # Initializes variables
  length = 1
  n_samples = len(vector)
  mean = numpy.ndarray((length,), 'float64')
  std = numpy.ndarray((length,), 'float64')
  mean.fill(0)
  std.fill(0)

  # Computes mean and variance
  for array in vector:
    x = array.astype('float64')
    mean += x
    std += (x ** 2)

  mean /= n_samples
  std /= n_samples
  std -= (mean ** 2)
  std = std ** 0.5
  arrayset = numpy.ndarray(shape=(n_samples,mean.shape[0]), dtype=numpy.float64)

  for i in range (0, n_samples):
    arrayset[i,:] = (vector[i]-mean) / std
  return arrayset