The .orientnew method is a little more compact here.

```python
A = ReferenceFrame{'A')
B = A.orientnew('B', 'Body', [alpha[0], beta[0], 0], 'ZXY')
```

Also please read through the PEP8 style guide if you haven't: http://www.python.org/dev/peps/pep-0008/

You should have spaces after you commas.