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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_x_y(collection_x, collection_y, filter_none=False):
 """ Merge two lists, creating a dictionary with key `label` and a set x and y """

    data = {}
    for item in collection_x:
        #print item[0:-1]
        #print item[-1]
        label = datetimeutil.tuple_to_string(item[0:-1])
        if filter_none and label == 'None-None':
            continue
        data[label] = {'label': label, 'x': item[-1], 'y': 0}
    for item in collection_y:
        #print item
        label = datetimeutil.tuple_to_string(item[0:-1])
        if filter_none and label == 'None-None':
            continue
        try:
            data[label]['y'] = item[-1]
        except KeyError:
            data[label] = {'label': label, 'x': 0, 'y': item[-1]}

    # Keys are not sorted
    return data