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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 _ensure_value_is_valid(self, value):
 """Ensure that value is a valid collection's value."""

        if not isinstance(value, self.__class__.value_type):
            raise TypeError('{0} is not valid collection value, instance '
                            'of {1} required'.format(
                                value, self.__class__.value_type))
        return value