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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 _none_value(self):
 """Get an appropriate "null" value for this field's type. This is used internally when setting the field to None. """

        if self.out_type == int:
            return 0
        elif self.out_type == float:
            return 0.0
        elif self.out_type == bool:
            return False
        elif self.out_type == six.text_type:
            return u''