Why might a KeyError occur even if I'm sure the key is in the dictionary?

By: USER7765
27 Agustus 2025 Support 5 minutes
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Grade: Education Subject: Support
Why might a KeyError occur even if I'm sure the key is in the dictionary?
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A KeyError can occur if the dictionary has been modified since you last checked for the key's existence. For example, another part of your code might have added or removed the key. Also, if the key's value is `None`, it might not be immediately obvious, and attempting to access it could still raise a KeyError.
Answered on 27 Agustus 2025

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