Error: DynamoDB Error Message KeyError item is not JSON serializable

Answered by Rafal Wilinski
What's Causing This Error
This error indicates that the JSON module cannot transform the specific item in question into a JSON-formatted string. It can occur when making a typographical error in the list of JSON data you are serializing.
Solution: Here's How To Resolve It
First, check and verify whether there is no syntax error in the specific key and unnecessary punctuation marks are not used. If there is any, it will result in causing a KeyError
because the key is unidentified.
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