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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 merge_figure(fig, subfig):
 """ Merge a sub-figure into a parent figure Note: This function mutates the input fig dict, but it does not mutate the subfig dict Parameters fig: dict The plotly figure dict into which the sub figure will be merged subfig: dict The plotly figure dict that will be copied and then merged into `fig` """


    # traces
    data = fig.setdefault('data', [])
    data.extend(copy.deepcopy(subfig.get('data', [])))

    # layout
    layout = fig.setdefault('layout', {})
    _merge_layout_objs(layout, subfig.get('layout', {}))