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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 process_teffs(self, teffs, coords, s=np.array([0., 0., 1.]), t=None):
 """ Change the local effective temperatures for any values within the "cone" defined by the spot. Any teff within the spot will have its current value multiplied by the "relteff" factor :parameter array teffs: array of teffs for computations :parameter array coords: array of coords for computations :t float: current time """

        if t is None:
            # then assume at t0
            t = self._t0

        pointing_vector = self.pointing_vector(s,t)
        logger.debug("spot.process_teffs at t={} with pointing_vector={} and radius={}".format(t, pointing_vector, self._radius))

        cos_alpha_coords = np.dot(coords, pointing_vector) / np.linalg.norm(coords, axis=1)
        cos_alpha_spot = np.cos(self._radius)

        filter_ = cos_alpha_coords > cos_alpha_spot
        teffs[filter_] = teffs[filter_] * self._relteff

        return teffs