code: def test_nested(self):
      @typecheck(
          x=int,
          y=oneof(
              nullable(str),
              sequenceof(sequenceof(dictof(oneof(str, int), anytype))),
          ),
      )
      def f(x, y):
          pass
  
      f(5, None)
      f(5, "7")
      f(5, [])
      f(5, [[]])
      f(5, [[{}]])
      f(5, [[{"6": None}]])
      f(5, [[{"6": None}]])
      f(5, [[{"6": None, 5: {1, 2, 3, 4}}]])
      self.assertRaises(TypeError, lambda: f(2, 2))
  
file_path: hail/hail/python/test/hail/typecheck/test_typecheck.py
imports: import unittest
  from hail.typecheck.check import *
label_desc: Use image node_id 3 for calling the Tests obj's underlying member method code with example usage: obj.test_nested() without return types