gis: Fixed #8207; now shield 2.4 test runners from attempting to import ctypes.

    HAS_GDAL, GEOJSON = False, False

# The envelope, error, and geomtype modules do not actually require the

#  GDAL library.

# GDAL library, but still nead at least Python 2.4 and ctypes.

PYTHON23 = sys.version_info[0] == 2 and sys.version_info[1] == 3

if not PYTHON23:

    try:

        from django.contrib.gis.gdal.envelope import Envelope

        from django.contrib.gis.gdal.error import check_err, OGRException, OGRIndexError, SRSException

        from django.contrib.gis.gdal.geomtype import OGRGeomType

    except ImportError:

        # No ctypes, but don't raise an exception.

        pass

    # Because the PostGIS version is checked when initializing the spatial 

    # backend a `ProgrammingError` will be raised if the PostGIS tables 

    # and functions are not installed.  We catch here so it won't be raised when 

    # running the Django test suite.

    from psycopg2 import ProgrammingError

    # running the Django test suite.  `ImportError` is also possible if no ctypes.

    try:

        from django.contrib.gis.db.backend.postgis.models import GeometryColumns, SpatialRefSys

    except ProgrammingError:

    except:

        _srid_info = False

elif not PYTHON23 and settings.DATABASE_ENGINE == 'oracle':

    # Same thing as above, except the GEOS library is attempted to be loaded for