y=x关于如何在使用 Altair时对双轴图表进行分面，然后向每个图表添加一条线，有什么建议吗？挑战在于，该线y=x需要与每个多面图表中显示的数据特定的系列比例相匹配。链接：Altair github 关于 Facets 的问题线程Altair github 轴显示上的问题线程下面是重现该问题的代码。import altair as altfrom vega_datasets import datasource = data.anscombe().copy()source['line-label'] = 'x=y'source = pd.concat([source,source.groupby('Series').agg(x_diff=('X','diff'), y_diff=('Y','diff'))],axis=1)source['rate'] = source.y_diff/source.x_diffsource['rate-label'] = 'rate-of-change'base = alt.Chart().encode(    x='X:O',)scatter = base.mark_circle(size=60, opacity=0.30).encode(    y='Y:Q',    color=alt.Color('Series:O', scale=alt.Scale(scheme='category10')),    tooltip=['Series','X','Y'])line_x_equals_y = alt.Chart().mark_line(color= 'black', strokeDash=[3,8]).encode(    x=alt.X('max(X)',axis=None),    y=alt.Y('max(X)',axis=None), # note: it's intentional to set max(X) here so that X and Y are equal.    color = alt.Color('line-label') # note: the intent here is for the line label to show up in the legend    )rate = base.mark_line(strokeDash=[5,3]).encode(    y=alt.Y('rate:Q'),    color = alt.Color('rate-label',),    tooltip=['rate','X','Y'])scatter_rate = alt.layer(scatter, rate, data=source)尝试过的解决方案问题：图表不是双轴（并且这不包括line_x_equals_y）scatter_rate.facet('Series',columns=2).resolve_axis(         x='independent',         y='independent',         )问题：Javascript 错误alt.layer(scatter_rate, line_x_equals_y, data=source).facet('Series',columns=2).resolve_axis(        x='independent',        y='independent',        )问题：Javascript 错误chart_generator =  (alt.layer(line_x_equals_y, scatter_rate, data = source, title=f"Series {val}").transform_filter(alt.datum.Series == val).resolve_scale(y='independent',x='independent') \             for val in source.Series.unique()) alt.concat(*(    chart_generator), columns=2)目标scatter_rate是一个多面（按系列）双轴图表，带有适合值范围的单独刻度。y=x每个多面图表都包含一条从 (0,0) 到y=max(X)各个图表的值的线。