问根据结果将多条线绘制成同一张图表，并以圆滑的方式表示。

EN

dfg = df.groupby([pd.Grouper(key='Date', freq='M'), 'direction']).size().to_frame('counts')
dfg.reset_index(inplace=True)
dfg.head()
Date    direction   counts
0   2015-02-28  Decreasing  4
1   2015-02-28  Increasing  5
2   2015-03-31  Decreasing  14
3   2015-03-31  Increasing  8
4   2015-04-30  Decreasing  12

import plotly.graph_objects as go

fig = go.Figure()

for d,c in zip(dfg['direction'].unique(), ['red','green']):
    dfs = dfg.query('direction == @d')
    fig.add_trace(
        go.Scatter(
            x=dfs['Date'],
            y=dfs['counts'],
            mode='lines',
            line=dict(
                color=c,
                width=3
            ),
            name=d
        )
    )

fig.show()