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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 get_hcurves_and_means(dstore):
 """ Extract hcurves from the datastore and compute their means. :returns: curves_by_rlz, mean_curves """

    rlzs_assoc = dstore['csm_info'].get_rlzs_assoc()
    getter = getters.PmapGetter(dstore, rlzs_assoc)
    pmaps = getter.get_pmaps()
    return dict(zip(getter.rlzs, pmaps)), dstore['hcurves/mean']