from django.contrib.gis.geos.geometry import GEOSGeometry, wkt_regex, hex_regex

 from django.contrib.gis.geos.point import Point

 from django.contrib.gis.geos.linestring import LineString, LinearRing

 from django.contrib.gis.geos.polygon import Polygon

 from django.contrib.gis.geos.collections import GeometryCollection, MultiPoint, MultiLineString, MultiPolygon

 from django.contrib.gis.geos.error import GEOSException, GEOSIndexError

 from django.contrib.gis.geos.libgeos import geos_version, geos_version_info, GEOS_PREPARE

 def fromfile(file_name):

     """

     Given a string file name, returns a GEOSGeometry. The file may contain WKB,

     WKT, or HEX.

     """

     fh = open(file_name, 'rb')

     buf = fh.read()

     fh.close()

     if wkt_regex.match(buf) or hex_regex.match(buf):

         return GEOSGeometry(buf)

     else:

         return GEOSGeometry(buffer(buf))

 def fromstr(wkt_or_hex, **kwargs):

     "Given a string value (wkt or hex), returns a GEOSGeometry object."

     return GEOSGeometry(wkt_or_hex, **kwargs)

 def hex_to_wkt(hex):

     "Converts HEXEWKB into WKT."

     return GEOSGeometry(hex).wkt

 def wkt_to_hex(wkt):

     "Converts WKT into HEXEWKB."

     return GEOSGeometry(wkt).hex

 def centroid(input):

     "Returns the centroid of the geometry (given in HEXEWKB)."

     return GEOSGeometry(input).centroid.wkt

 def area(input):

     "Returns the area of the geometry (given in HEXEWKB)."

     return GEOSGeometry(input).area