// variable passed with input index. The caller takes ownership of the `source`
// and `dest` tensors and is responsible for freeing them with TF_DeleteTensor.
TF_CAPI_EXPORT extern void TF_GetInputTensorFromVariable(
    TF_OpKernelContext* ctx, int input, bool lock_held, bool isVariantType,
    bool sparse,
    void (*copyFunc)(TF_OpKernelContext* ctx, TF_Tensor* source,
                     TF_Tensor* dest),