This method overrides django.contrib.gis.geos.geometry.GEOSGeometryBase.__init__.
* strings:
- WKT
- HEXEWKB (a PostGIS-specific canonical form)
- GeoJSON (requires GDAL)
* buffer:
- WKB
The `srid` keyword specifies the Source Reference Identifier (SRID)
number for this Geometry. If not provided, it defaults to None.This method is overriden in: