"No module named 'keras.engine'" Error in Mask R-CNN: A Troubleshooting Guide
Problem: You're trying to implement a Mask R-CNN model using TensorFlow and Keras, but you encounter the error "No module named 'keras.engine'". This error message indicates that Python can't find the keras.engine module, which is essential for building neural network models in Keras.
Understanding the Error:
The error "No module named 'keras.engine'" usually stems from an outdated or incompatible Keras installation. In recent Keras versions, the keras.engine module has been restructured and is no longer accessible directly. This change is due to the integration of Keras with TensorFlow 2.0 and the adoption of a more modular structure.
The Scenario:
Let's say you're working on a Mask R-CNN project and your code includes the following line:
from keras.engine.topology import Layer
This code attempts to import the Layer class from the keras.engine.topology module, but you encounter the dreaded "No module named 'keras.engine'" error.
Troubleshooting Steps:
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Update Keras: The most common reason for this error is an outdated Keras installation. Update your Keras library to the latest version using pip:
pip install --upgrade keras -
Check for Multiple Keras Installations: Occasionally, you might have conflicting Keras installations from different environments (like Anaconda and your system's default Python). Make sure you're using the correct environment and that your project is using the updated Keras version.
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Verify TensorFlow Installation: Since Keras relies heavily on TensorFlow, ensure that TensorFlow is correctly installed and activated. If you're using TensorFlow 2.0 or later, you should have Keras automatically included.
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Import the
kerasmodule correctly: When importing Keras modules, use thetensorflow.kerasnamespace for TensorFlow 2.0 and above. For example:from tensorflow.keras.layers import LayerThis change reflects the new structure of Keras and ensures you're accessing the correct modules.
-
Restart Your Kernel (If Necessary): After making changes to your Keras installation or environment, restarting your Python kernel or IDE often resolves import issues.
Example of a Corrected Code Snippet:
from tensorflow.keras.layers import Layer
Additional Insights:
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It's a good practice to keep your development environment up to date. Use
pip install --upgrade pipto ensure you have the latest version of pip for managing packages. -
Consult the official Keras documentation for detailed information on the latest API changes and recommended import practices.
Conclusion:
The "No module named 'keras.engine'" error is typically caused by an outdated Keras installation or incorrect import syntax. By following the troubleshooting steps outlined above, you can resolve this issue and continue working on your Mask R-CNN project effectively. Remember to update your Keras version, ensure proper TensorFlow installation, and adjust your imports to match the latest Keras structure.
Resources:
- Keras Documentation: https://keras.io/
- TensorFlow Documentation: https://www.tensorflow.org/
- Mask R-CNN Tutorial: https://github.com/matterport/Mask_RCNN
