code: def logp_gradient_of_set(variable_set, calculation_set=None):
      
  
      logp_gradients = {}
      for variable in variable_set:
          logp_gradients[variable] = logp_gradient(variable, calculation_set)
  
      return logp_gradients
docs: Calculates the gradient of the joint log posterior with respect to all the variables in variable_set.
      Calculation of the log posterior is restricted to the variables in calculation_set.
  
      Returns a dictionary of the gradients.