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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 srs_check(ds):
 """Check validitiy of Dataset srs Return True if srs is properly defined """

    # ds_srs = get_ds_srs(ds)
    gt = np.array(ds.GetGeoTransform())
    gt_check = ~np.all(gt == np.array((0.0, 1.0, 0.0, 0.0, 0.0, 1.0)))
    proj_check = (ds.GetProjection() != '')
    #proj_check = ds_srs.IsProjected()
    out = False
    if gt_check and proj_check:  
        out = True
    return out