import plotly.express as px
df = px.data.iris()
fig = px.scatter(df, x="petal_length", y="petal_width")
fig.add_vline(x=2.5, line_width=3, line_dash="dash", line_color="green")
fig.add_hrect(y0=0.9, y1=2.6, line_width=0, fillcolor="red", opacity=0.2)
fig.show()