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python - Unable to query a local variable in pandas 0.14.0

I can query an explicit value:

fills.query('Symbol=="BUD US"')

Now I want to query a variable:

In [40]: my_symbol
Out[40]: 'BUD US'

In pandas 0.13.1, I could simply use:

fills.query('Symbol==my_symbol')

This is no longer permitted in pandas 0.14.0 because local variables must be referred to explicitly. So I tried

fills.query('Symbol==@my_symbol')

but this returned an error

KeyError: '__pd_eval_local_my_symbol'

I was able to change some of my other code to use explicit local variables, but this one just will not take. Any thoughts? The dtype is object, if that helps.

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Seems a bug in 0.14, specifically with strings (works eg with ints). I filed an issue here: https://github.com/pydata/pandas/issues/7300.
As a workaround for now, you can wrap it in a list:

In [40]: fills
Out[40]: 
    Price  Symbol
0  109.70  BUD US
1  109.72  BUD US
2  183.30  IBM US
3  183.35  IBM US

In [41]: my_symbol = ['BUD US']

In [42]: fills.query('Symbol==@my_symbol')
Out[42]: 
    Price  Symbol
0  109.70  BUD US
1  109.72  BUD US

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