def env_func(f, argtypes):
    f.argtypes = argtypes
    f.restype = None
    f.errcheck = check_envelope
    return f
For getting OGREnvelopes.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/contrib/gis/gdal/prototypes/geom.py/env_func