[pypy-issue] Issue #2621: Ctypes Structure doesn`t support duplicate field names (pypy/pypy)

[Mihnea Saracin]

New issue 2621: Ctypes Structure doesn`t support duplicate field names
https://bitbucket.org/pypy/pypy/issues/2621/ctypes-structure-doesn-t-support-duplicate

Mihnea Saracin:

When I try to run the attached script, it gives the following result only for PyPy . But on Cpython this is legitimate code.
```
#!python
ValueError: duplicate field name a
```
The script is part of ctypes/test/test_byteswap.py lines 168-186