This dictionary expression binds the same key multiple times. This may lead to unintentional behaviour as the key will always map the last value provided to it. It is recommended to have unique keys.

Bad practice

Here, the key random is provided twice.

DICT = {
    "some": "some",
    "random": "random",
    "dict": "dict",
    "values": "values",
    "random": "different",
}

Recommended

All keys should be unique.

DICT = {
    "some": "some",
    "dict": "dict",
    "values": "values",
    "random": "different",
}