docstr: If you need to restrict parameters
  For example, variances should be > 0
  Parameters maybe have to be within -1 and 1
code: def transform_params(self, unconstrained):
      """
      If you need to restrict parameters
      For example, variances should be > 0
      Parameters maybe have to be within -1 and 1
      """
      constrained = unconstrained.copy()
      constrained[self.positive_parameters] = (
          constrained[self.positive_parameters] ** 2
      )
      return constrained
  
imports: from collections import OrderedDict
  import matplotlib.pyplot
  import numpy
  import pandas
  import statsmodels.api
  import pymc3
  import theano
  import theano.tensor
label_desc: Use image node_id 4 for calling the MultipleYsModel obj's underlying member method code with example usage: obj.transform_params(unconstrained) and returns: constrained