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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:

async def serialize(self, value, native=False):
        '''
        Calls the field's ``to_python`` method.
        Override in derived classes of fields which involve models, such as ``ModelField``
        '''
        if native:
            return self.to_python(value)
        return self.to_data(value)