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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 fov(self, values):
 """ Set the field of view in degrees. Parameters values : (2,) float Size of FOV to set in degrees """

        if values is None:
            self._fov = None
        else:
            values = np.asanyarray(values, dtype=np.float64)
            if values.shape != (2,):
                raise ValueError('focal length must be (2,) int')
            # assign passed values to FOV
            self._fov = values
            # fov overrides focal
            self._focal = None