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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 _compute_fixed(self):
        '''Recompute any fixed quantities after a change in parameters'''
        try:
            lon, lat = np.meshgrid(self.lon, self.lat)
        except:
            lat = self.lat
        phi = np.deg2rad(lat)
        try:
            albedo = self.a0 + self.a2 * P2(np.sin(phi))
        except:
            albedo = np.zeros_like(phi)
        # make sure that the diagnostic has the correct field dimensions.
        #dom = self.domains['default']
        #  this is a more robust way to get the single value from dictionary:
        dom = next(iter(self.domains.values()))
        self.albedo = Field(albedo, domain=dom)