error: Argument 1 to "find" of "bytearray" has incompatible type "int"; expected "bytes"

Source code:
```
ba = bytearray('012}'.encode())
print(ba.find(125))
```

mypy error:
```
$ python -m mypy _test.py
_test.py:2: error: Argument 1 to "find" of "bytearray" has incompatible type "int"; expected "bytes"
```

Am I doing something wrong or is this some mypy (or maybe python) issue?

Thanks!

mypy 0.470
python 3.6