how to group dataframe by date on multiple cplumns

<code python>
df1 = a.groupby(['date'])['price'].agg(['first','max', 'min', 'last'])
df2 = a.groupby(['date'])['volume'].agg(['sum'])
df3 = pd.concat([df1, df2[['sum']]], axis=1)
df3.head()

df3a = a.groupby('date').agg({'price': ['first','max', 'min', 'last'],'volume': ['sum']})
</code>

to aggreage by date
<code python>
# create daily
df1 = a.groupby([a['date'].dt.date]).agg({'price': ['first','max', 'min', 'last'],'volume': ['sum']})
df1.head()
df1.plot()
</code>