I get some code as followed:

```
train_df['Age'].isnull().value_counts()

```

```
False    714
True     177
Name: Age, dtype: int64

```

So I am wondering how to count null values and nonnull values with 0 and 1 as row index not False and True in Pandas, which should output as followed:

```
0    714
1    177
Name: Age, dtype: int64

```

I know maybe I can generate a new DataFrame and change the row index, but it seems like complex.  

So could anyone help me and give me a concise way?  

Thanks in advance.