MutableOperandRange getArgOperandsMutable() {
      return getArgsMutable();
    }

    // Returns the callee of this operation.
    CallInterfaceCallable getCallableForCallee() { return getFAttr(); }
    // Sets the callee from the callable.
    void setCalleeFromCallable(CallInterfaceCallable callee);

    // returns the callee of this operation.
    func::FuncOp func() {