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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 mmi_ramp_roman(raster_layer):
 """Generate an mmi ramp using range of 1-10 on roman. A standarised range is used so that two shakemaps of different intensities can be properly compared visually with colours stretched accross the same range. The colours used are the 'standard' colours commonly shown for the mercalli scale e.g. on wikipedia and other sources. :param raster_layer: A raster layer that will have an mmi style applied. :type raster_layer: QgsRasterLayer .. versionadded:: 4.0 """


    items = []
    sorted_mmi_scale = sorted(
        earthquake_mmi_scale['classes'], key=itemgetter('value'))
    for class_max in sorted_mmi_scale:
        colour = class_max['color']
        label = '%s' % class_max['key']
        ramp_item = QgsColorRampShader.ColorRampItem(
            class_max['value'], colour, label)
        items.append(ramp_item)

    raster_shader = QgsRasterShader()
    ramp_shader = QgsColorRampShader()
    ramp_shader.setColorRampType(QgsColorRampShader.Interpolated)
    ramp_shader.setColorRampItemList(items)
    raster_shader.setRasterShaderFunction(ramp_shader)
    band = 1
    renderer = QgsSingleBandPseudoColorRenderer(
        raster_layer.dataProvider(),
        band,
        raster_shader)
    raster_layer.setRenderer(renderer)