'Convert the name of an extension (eg. "foo.bar") into the name
of the file from which it will be loaded (eg. "foo/bar.so", or
"foo\bar.pyd").'

def get_ext_filename(self, ext_name):

    from distutils.sysconfig import get_config_var
    ext_path = ext_name.split('.')
    ext_suffix = get_config_var('EXT_SUFFIX')
    return (os.path.join(*ext_path) + ext_suffix)
