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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 buy_on_drop(symbol_set="sp5002012", 
            dataobj=dataobj, 
            start=datetime.datetime(2008, 1, 3), 
            end=datetime.datetime(2009, 12, 28),
            market_sym='$SPX',
            threshold=6,
            sell_delay=5,
            ):
    '''Compute and display an "event profile" for multiple sets of symbols'''
    if symbol_set:
        if isinstance(symbol_set, basestring):
            if symbol_set.lower().startswith('sp'):
                symbol_set = dataobj.get_symbols_from_list(symbol_set.lower())
            else:
                symbol_set = [sym.stip().upper() for sym in symbol_set.split(",")]
    else:
        symbol_set = dataobj.get_symbols_from_list("sp5002012")
    if market_sym:
        symbol_set.append(market_sym)

    print "Starting Event Study, retrieving data for the {0} symbol list...".format(symbol_set)
    market_data = get_clean_prices(symbol_set, dataobj=dataobj, start=start, end=end)
    print "Finding events for {0} symbols between {1} and {2}...".format(len(symbol_set), start, end)
    trigger_kwargs={'threshold': threshold}
    events = find_events(symbol_set, market_data,  market_sym=market_sym, trigger=drop_below, trigger_kwargs=trigger_kwargs)

    csvwriter = csv.writer(getattr(args, 'outfile', open('buy_on_drop_outfile.csv', 'w')), dialect='excel', quoting=csv.QUOTE_MINIMAL)
    for order in generate_orders(events, sell_delay=sell_delay, sep=None):
        csvwriter.writerow(order)

    print "Creating Study report for {0} events...".format(len(events))
    ep.eventprofiler(events, market_data, 
                         i_lookback=20, i_lookforward=20,
                         s_filename='Event report--buy on drop below {0} for {1} symbols.pdf'.format(threshold, len(symbol_set)),
                         b_market_neutral=True,
                         b_errorbars=True,
                         s_market_sym=market_sym,
                         )
    return events