import pandas

df = pandas.read_csv('test.csv')

# print(df[df['나이'] > 21])
print(df[df['나이'].notnull()])
aedb11af7a479d6541336b77e6b6ce78270a660c
<mask token>

<mask token>
print(df[df['나이'].notnull()])

<mask token>
df = pandas.read_csv('test.csv')
print(df[df['나이'].notnull()])

import pandas
df = pandas.read_csv('test.csv')
print(df[df['나이'].notnull()])

import pandas

df = pandas.read_csv('test.csv')

# print(df[df['나이'] > 21])
print(df[df['나이'].notnull()])