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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 allocate_series_dataframes(network, series):
 """ Populate time-varying outputs with default values. Parameters network : pypsa.Network series : dict Dictionary of components and their attributes to populate (see example) Returns ------- None Examples -------- 'Load': ['p']}) """


    for component, attributes in iteritems(series):

        df = network.df(component)
        pnl = network.pnl(component)

        for attr in attributes:
            pnl[attr] = pnl[attr].reindex(columns=df.index,
                                          fill_value=network.components[component]["attrs"].at[attr,"default"])