PyArrow array type translation seems to not be correct

The type numbers seem off when translating PyArrow arrays using PyArrow 3.0.

I did a bit of debugging and found the following for example:
```
Object to be extracted: TimestampType(timestamp[ns])  id: Ok(18)
Object to be extracted: DataType(string)  id: Ok(13)
Object to be extracted: DataType(int32)  id: Ok(7)
```

(This is by adding debugging to `extract()` function)