how to get the ratio of missing values in pandas df column in python

main.py
import pandas as pd

# create sample dataframe
df = pd.DataFrame({'A': [1, 2, None, 4, None],
                   'B': [None, 6, 7, None, 9],
                   'C': ['a', 'b', None, 'd', 'e']})

# calculate ratio of missing values in each column
missing_value_ratios = df.isna().mean()

# print the missing_value_ratios
print(missing_value_ratios)
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main.py
A    0.4
B    0.4
C    0.2
dtype: float64
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