code: def verify_constraints(constraints):
          
          # verify return is a list
          if not isinstance(constraints, list):
              raise ValueError(
                  "invalid type returned by make_constraints: %r (must be a list)" % constraints
              )
  
          # verify each list element is a Constraint instance
          for constraint in constraints:
              if not isinstance(constraint, Constraint):
                  raise ValueError(
                      "invalid constraint type: %r (must be a Constriant)" % constraint
                  )
docs: Verify values returned from :meth:`make_constraints`.
  
          Used internally during the :meth:`build` process.
  
          :param constraints: value returned from :meth:`make_constraints`
          :type constraints: :class:`list`
          :raises ValueError: if verification fails