>>> import pandas as pd
>>> import numpy as np
>>> import altair as alt
>>>
>>> df = pd.DataFrame(
...     np.random.randn(200, 3),
...     columns=['a', 'b', 'c'])
...
>>> c = alt.Chart(df).mark_circle().encode(
...     x='a', y='b', size='c', color='c', tooltip=['a', 'b', 'c'])
>>>
>>> st.write(c)