error at shake 256 and 512 mode

[chezsick]

each time i type :::: vanityhash -d shake_256 000000
output ::::

Traceback (most recent call last):
  File "/usr/local/bin/vanityhash", line 612, in <module>
    vh.main()
  File "/usr/local/bin/vanityhash", line 118, in main
    self.args = self.parse_args()
  File "/usr/local/bin/vanityhash", line 463, in parse_args
    hexdigestsize = len(testctx.hexdigest(*self.digest_args, **self.digest_kwargs))
TypeError: hexdigest() takes exactly one argument (0 given)

pleaese fix it!
Sick.