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- Use repr to represent all JSON fields of unknown types by default.
Previously, when passing a mapping (dictionary) as a log message,
watchtower would replace datetime objects with their “.isoformat()”
string representation, and would replace all other
non-JSON-serializable objects with ``null``. The new behavior is to
use the output of repr() to represent these non-JSON-serializable
objects. This change may cause your logger to log more data than you
intended, which is why it triggers a major version bump. If you use
watchtower to log sensitive information or objects with large repr
strings, you are advised to examine your log messages to see if any
newly visible data should be sanitized. If you need to customize this
behavior, you can pass a custom JSON default serializer using the
``json_serialize_default`` keyword argument.