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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def postgis_type(self):
 """ Get the type of the geometry in PostGIS format, including additional dimensions and SRID if they exist. """

        dimz = "Z" if self.dimz else ""
        dimm = "M" if self.dimm else ""
        if self.srid:
            return "geometry({}{}{},{})".format(self.type, dimz, dimm, self.srid)
        else:
            return "geometry({}{}{})".format(self.type, dimz, dimm)