Tiny ML on Arduino: Gesture recognition tutorial results in a blank model.h

I attempted to run through the Tiny ML on Arduino: Gesture recognition example and it resulted in a a model.h file that is just a model array declaration.

Ex:
```
const unsigned char model[] = {
};

```

This is the example that I was following:
[https://colab.research.google.com/github/arduino/ArduinoTensorFlowLiteTutorials/blob/master/GestureToEmoji/arduino_tinyml_workshop.ipynb#scrollTo=f92-4Hjy7kA8](url)

The following Warnings were seen while running the example:
NOTE: An issue was filed with the Colab project but I do not see it listed.

Also, a gesture_model.tflite file was created and has about 145K of data.

- Setup Python Environment

```
E: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/v/vim/xxd_8.0.1453-1ubuntu1.1_amd64.deb 404 Not Found [IP: 91.189.88.152 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

```

- Build & Train the Model
```
Train on 12 samples, validate on 4 samples
Epoch 1/600
WARNING:tensorflow:Entity .initialize_variables at 0x7fe172912ae8> could not be transformed and will be executed as-is. Please report this to the AutoGraph team. When filing the bug, set the verbosity to 10 (on Linux, `export AUTOGRAPH_VERBOSITY=10`) and attach the full output. Cause: module 'gast' has no attribute 'Num'
WARNING: Entity .initialize_variables at 0x7fe172912ae8> could not be transformed and will be executed as-is. Please report this to the AutoGraph team. When filing the bug, set the verbosity to 10 (on Linux, `export AUTOGRAPH_VERBOSITY=10`) and attach the full output. Cause: module 'gast' has no attribute 'Num'
12/12 [==============================] - 1s 50ms/sample - loss: 0.3119 - mae: 0.5501 - val_loss: 0.2502 - val_mae: 0.4998
Epoch 2/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2653 - mae: 0.5116 - val_loss: 0.2498 - val_mae: 0.4994
Epoch 3/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2620 - mae: 0.5116 - val_loss: 0.2493 - val_mae: 0.4991
Epoch 4/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2628 - mae: 0.5082 - val_loss: 0.2488 - val_mae: 0.4985
Epoch 5/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2569 - mae: 0.5058 - val_loss: 0.2443 - val_mae: 0.4942
Epoch 6/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2553 - mae: 0.4992 - val_loss: 0.2579 - val_mae: 0.4993
Epoch 7/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2619 - mae: 0.5072 - val_loss: 0.2531 - val_mae: 0.4989
Epoch 8/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2576 - mae: 0.5051 - val_loss: 0.2521 - val_mae: 0.4983
Epoch 9/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2569 - mae: 0.5049 - val_loss: 0.2499 - val_mae: 0.4981
Epoch 10/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2544 - mae: 0.5036 - val_loss: 0.2491 - val_mae: 0.4979
Epoch 11/600
12/12 [==============================] - 0s 3ms/sample - loss: 0.2533 - mae: 0.5029 - val_loss: 0.2485 - val_mae: 0.4978
```

- Run with Test Data
```
/usr/local/lib/python3.6/dist-packages/ipykernel_launcher.py:10: MatplotlibDeprecationWarning: cycling among columns of inputs with non-matching shapes is deprecated.
# Remove the CWD from sys.path while we load stuff.
/usr/local/lib/python3.6/dist-packages/ipykernel_launcher.py:11: MatplotlibDeprecationWarning: cycling among columns of inputs with non-matching shapes is deprecated.
# This is added back by InteractiveShellApp.init_path()

```

- Convert the Trained Model to Tensor Flow Lite
```
WARNING:tensorflow:Entity .initialize_variables at 0x7fe16a17d598> could not be transformed and will be executed as-is. Please report this to the AutoGraph team. When filing the bug, set the verbosity to 10 (on Linux, `export AUTOGRAPH_VERBOSITY=10`) and attach the full output. Cause: module 'gast' has no attribute 'Num'
WARNING: Entity .initialize_variables at 0x7fe16a17d598> could not be transformed and will be executed as-is. Please report this to the AutoGraph team. When filing the bug, set the verbosity to 10 (on Linux, `export AUTOGRAPH_VERBOSITY=10`) and attach the full output. Cause: module 'gast' has no attribute 'Num'
Model is 147764 bytes
```

Bắt đầu với arduino_tinyml_workshop.ipynb được liên kết và so sánh bước Convert the Trained Model to TensorFlow Lite với model.h được tạo ra. Kiểm tra lý do notebook tạo ra một mảng trống mặc dù gesture_model.tflite được báo cáo có kích thước 147764 byte; hoàn thành có nghĩa là tutorial tạo ra một model.h không rỗng, phù hợp với ví dụ Arduino.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.