[Python] Truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or...

I want to filter my dataframe with an or condition to keep rows with a particular column's values that are outside the range [-0.25, 0.25]. I tried:

df = df[(df['col'] < -0.25) or (df['col'] > 0.25)]


But I get the error:

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
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