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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 _set_band_and_valid_mask(self):
 """ Downloads band data and valid mask. Sets parameters self.bands, self.valid_data """

        data = np.asarray(self.ogc_request.get_data())
        self.bands = data[..., :-1]
        self.valid_data = (data[..., -1] == 1.0).astype(np.bool)