return;
    }
    absl::MutexLock lock(&mu_);
    InsertLocked(key, value);
  }

  // Delete the entry with key `key`. Return true if the entry was found for
  // `key`, false if the entry was not found. In both cases, there is no entry
  // with key `key` existed after the call.
  bool Delete(const std::string& key) {
    absl::MutexLock lock(&mu_);
    return DeleteLocked(key);
  }

TF_CAPI_EXPORT extern void TF_CreateDir(const char* dirname, TF_Status* status);

// Deletes the specified directory. Typical status codes are:
//  * TF_OK - successfully deleted the directory
//  * TF_FAILED_PRECONDITION - the directory is not empty
TF_CAPI_EXPORT extern void TF_DeleteDir(const char* dirname, TF_Status* status);

// Deletes the specified directory and all subdirectories and files underneath

	virtual std::string run() { return "Callback::run"; }
};

class Caller {
private:
	Callback *callback_;
public:
	Caller(): callback_(0) { }
	~Caller() { delCallback(); }
	void delCallback() { delete callback_; callback_ = 0; }
	void setCallback(Callback *cb) { delCallback(); callback_ = cb; }
	std::string call();

//
// WARNING: Since the underlying object could be ref-counted a user of this
// interface cannot destruct the underlying operation object. Instead, call
// TFE_DeleteOp who calls Release() on the operation pointer and deletes
// the TFE_Op structure.
typedef struct TFE_Op TFE_Op;

namespace tensorflow {

DEFINE_CONVERSION_FUNCTIONS(tensorflow::ImmediateExecutionOperation, TFE_Op);

//
// WARNING: Since the underlying object could be ref-counted a user of this
// interface cannot destruct the underlying handle object. Instead, call
// TFE_DeleteTensorHandle who calls Release() on the handle pointer and deletes
// the TFE_TensorHandle structure.
typedef struct TFE_TensorHandle TFE_TensorHandle;

namespace tensorflow {

DEFINE_CONVERSION_FUNCTIONS(tensorflow::ImmediateExecutionTensorHandle,

                         TF_Status* s);

// Creates a new TF_AbstractFunction from the current tracing states in the
// context. The provided `ctx` is consumed by this API call and deleted.
// The returned TF_AbstractFunction must be deleted by the client,
// TODO(aminim): clarify the contract on the state of the context after this
// call.
TF_AbstractFunction* TF_FinalizeFunction(TF_ExecutionContext* ctx,

      read_only_memory_region_ops_;
  std::function<void*(size_t)> plugin_memory_allocate_;
  std::function<void(void*)> plugin_memory_free_;
  ModularFileSystem(const ModularFileSystem&) = delete;
  void operator=(const ModularFileSystem&) = delete;
};

class ModularRandomAccessFile final : public RandomAccessFile {
 public:
  ModularRandomAccessFile(const std::string& filename,

// opaque pointer, since TensorFlow cannot parse it). `delete_func` is needed
// for ResourceMgr to clean up the resource. `status` will be set.
TF_CAPI_EXPORT extern void TF_CreatePluginResource(
    TF_OpKernelContext* ctx, const char* container_name,
    const char* plugin_resource_name, void* plugin_resource,
    void (*delete_func)(void*), TF_Status* status);

  std::unique_ptr<TensorSliceReader::VarToShapeMap> var_to_shape_map_;
  std::unique_ptr<TensorSliceReader::VarToDataTypeMap> var_to_data_type_map_;

  CheckpointReader(const CheckpointReader&) = delete;
  void operator=(const CheckpointReader&) = delete;
};

}  // namespace checkpoint
}  // namespace tensorflow

  // TF_DeleteSession.
  // TF_Graph may only / must be deleted when
  //   sessions.size() == 0 && delete_requested == true
  //
  // TODO(b/74949947): mutations currently trigger a warning instead of a bad
  // status, this should be reverted when possible.
  tensorflow::gtl::FlatMap<TF_Session*, tensorflow::string> sessions
      TF_GUARDED_BY(mu);
  bool delete_requested TF_GUARDED_BY(mu);  // set true by TF_DeleteGraph