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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 view_global_hcurves(token, dstore):
 """ Display the global hazard curves for the calculation. They are used for debugging purposes when comparing the results of two calculations. They are the mean over the sites of the mean hazard curves. """

    oq = dstore['oqparam']
    nsites = len(dstore['sitecol'])
    rlzs_assoc = dstore['csm_info'].get_rlzs_assoc()
    mean = getters.PmapGetter(dstore, rlzs_assoc).get_mean()
    array = calc.convert_to_array(mean, nsites, oq.imtls)
    res = numpy.zeros(1, array.dtype)
    for name in array.dtype.names:
        res[name] = array[name].mean()
    return rst_table(res)