code: def _modeldesc_to_dict(self, md):
          
          d = {'lhs_termlist': [md.lhs_termlist[0].factors[0].name()]}
          rhs_termlist = []
  
          # add other terms, if any
          for term in md.rhs_termlist[:]:
              if len(term.factors) == 0:
                  # intercept, represent by empty string
                  rhs_termlist.append('')
              else:
                  rhs_termlist.append(term.factors[0].name())
  
          d['rhs_termlist'] = rhs_termlist
          return d
docs: Return a string representation of a patsy ModelDesc object