class_docstr: Fuse multiple iterators by summing them with scaling.
  
  result = sum(args) + base
  
  Parameters
  ----------
  args : List[IterSplitExpr]
      The input to the sum expression.
  
  base : PrimExpr
      The base offset.
code: def __init__(self, args, base):
      self.__init_handle_by_constructor__(
          _ffi_api.IterSumExpr, args, base
      )
  
imports: from enum import IntEnum
  import tvm._ffi
  from tvm.runtime import Object
  from tvm.ir import PrimExpr
  from .None import _ffi_api
label_desc: Use image node_id 1 to create a new IterSumExpr object from inherited base classes: IterMapExpr with example: obj = IterSumExpr(args, base)