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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _assert_validators(self, validators):
 """Asserts if all validators in the list are satisfied. It asserts validators in the order they were created. Args: validators: Iterable(validators.Validator), validators to be verified. Raises: AttributeError: Raised if validators work with a non-existing flag. IllegalFlagValueError: Raised if validation fails for at least one validator. """

    for validator in sorted(
        validators, key=lambda validator: validator.insertion_index):
      try:
        validator.verify(self)
      except _exceptions.ValidationError as e:
        message = validator.print_flags_with_values(self)
        raise _exceptions.IllegalFlagValueError('%s: %s' % (message, str(e)))