@register.tag
def nicknames(parser, token):
  node = nickname(parser, token)
  node.is_multi = True
  return node
normalize the random variable, i.e. subtract mean and rescale
dataset/ETHPy150Open rietveld-codereview/rietveld/codereview/library.py/nicknames--crossover with--dataset/ETHPy150Open statsmodels/statsmodels/statsmodels/sandbox/distributions/mv_normal.py/MVElliptical.normalize