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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 validate_to_one(self, value):
 """ Check if the to_one should exist & casts properly """


        if value.rid and self.typeness is int:
            validators.validate_int(value)

        if value.rid and not self.skip_exists:
            if not value.load():
                raise ValidationError(self.messages['exists'])
        return value