Error in docstring for pandas/core/frame.py

[alphaCTzo7G]

There is an error in the docstring for the query function in

pandas/core/frame.py.

The PR here fixes this: #21731

Code Sample, a copy-pastable example if possible

# Your code here

Problem description

[this should explain why the current behaviour is a problem and why the expected output is a better solution.]

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Expected Output

Output of pd.show_versions()

[paste the output of pd.show_versions() here below this line]