code: def total_sensitivity_index(a, alpha=None):
      a = np.array(a)
  
      pv = _partial_first_order_variance(a, alpha)
      tv = _total_variance(a, alpha)
      product_pv = np.product(1 + pv, axis=0)
  
      return np.divide(pv * np.divide(product_pv, 1 + pv.T), tv)
  
imports: import numpy
label_desc: Use image node_id 5 for calling a global function with example usage: total_sensitivity_index(a, alpha) and returns: np