[Python] Pandas filter string data based on its string length using DataFrame.query

The question is very similar to this question Python: Pandas filter string data based on its string length, but I want to use pandas.DataFrame.query. Let's say we have a pandas.DataFrame. I like to filter out the rows where the string length of the column A is not equal to 3 using pandas.DataFrame.query

import pandas as pd
import numpy as np
df = pd.DataFrame({'A' : ['hi', 'hello', 'day', np.nan], 'B' : [1, 2, 3, 4]})
df.query('A.str.len() != 3')


However, I got the following error

TypeError: unhashable type: 'numpy.ndarray'

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