code: def bound_type_vars(expr, mod=None):
      """Get bound type variables from expression/type e
  
      Parameters
      ----------
      expr : Union[tvm.relay.Expr,tvm.relay.Type]
          The input expression/type
  
      mod : Optional[tvm.IRModule]
          The global module
  
      Returns
      -------
      free : List[tvm.relay.TypeVar]
          The list of bound type variables in post-DFS order
      """
      use_mod = mod if mod is not None else IRModule()
      return _ffi_api.bound_type_vars(expr, use_mod)
  
imports: from ...ir import IRModule
  from ...relay import transform, build_module
  from ...runtime.ndarray import cpu
  from .None import _ffi_api
  from .feature import Feature
label_desc: Use image node_id 10 for calling a global function with example usage: bound_type_vars(expr, mod) and returns: _ffi_api