如何删除bokeh表中的NaN

from bokeh.models import ColumnDataSource
from bokeh.plotting import figure, show
from bokeh.io import output_notebook
import pandas as pd

data = {'x': [1, 2, 3, 4, float('nan'), 6, 7, 8, 9, 10],
        'y': [11, 12, 13, float('nan'), 15, 16, 17, 18, 19, 20]}
df = pd.DataFrame(data)

df = df.dropna()

output_notebook()  # 在Jupyter Notebook中显示图表

source = ColumnDataSource(df)
p = figure()
p.circle(x='x', y='y', source=source)
show(p)