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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 get_value(self, field_name):
 """ returns a value for a given field name """

        if field_name in self.fields:
            return self._dict['attributes'][field_name]
        elif field_name.upper() in ['SHAPE', 'SHAPE@', "GEOMETRY"]:
            return self._dict['geometry']
        return None