def show_profit_attribution(round_trips):
total_pnl = round_trips['<STR_LIT>'].sum()<EOL>pnl_attribution = round_trips.groupby('<STR_LIT>')['<STR_LIT>'].sum() / total_pnl<EOL>pnl_attribution.name = '<STR_LIT>'<EOL>pnl_attribution.index = pnl_attribution.index.map(utils.format_asset)<EOL>utils.print_table(<EOL>pnl_attribution.sort_values(<EOL>inplace=False,<EOL>ascending=False,<EOL>),<EOL>name='<STR_LIT>',<EOL>float_format='<STR_LIT>'.format,<EOL>)<EOL>
Prints the share of total PnL contributed by each
traded name.

Parameters
----------
round_trips : pd.DataFrame
    DataFrame with one row per round trip trade.
    - See full explanation in round_trips.extract_round_trips
ax : matplotlib.Axes, optional
    Axes upon which to plot.

Returns
-------
ax : matplotlib.Axes
    The axes that were plotted on.