"Library Import Failure – Issue #1188"
Error Description: When running the project, the following issues were observed:
CUDA Warnings: Indicated missing GPU drivers, forcing CPU fallback.
Library Registration Errors: Failed to register cuFFT, cuDNN, and cuBLAS (non-critical but worth noting).
Deprecation Warnings: TensorFlow flagged deprecated usage of resource variables.
Fatal ImportError:
ImportError: cannot import name 'is_sequence' from 'tensorflow.python.util.nest'
This halted execution.
Root Cause Analysis: TFLearn relies on is_sequence from tensorflow.python.util.nest.
TensorFlow 2.x+ removed or relocated this utility as part of API refactoring.
Broken Dependency: TFLearn’s outdated import fails on modern TensorFlow installations.
Solution Implemented:
- Code Fix (PR Submitted) Modified the import to use TensorFlow’s current public API:
Before (broken):
from tensorflow.python.util.nest import is_sequence
After (fixed):
from tensorflow.pydoc import is_sequence # or alternative stable API
(Note: Exact replacement depends on TF version. Alternatives include tf.nest.is_sequence or tf_utils.is_sequence.)
- Validation Steps: Confirmed the fix works on:
TensorFlow >=2.6.0
Python 3.8+
Verified GPU/CPU mode post-fix (if applicable).
- Mitigation for Users: If unable to wait for the PR merge:
Option 1: Pin TensorFlow to a compatible version:
pip install "tensorflow<2.6.0" # or version where is_sequence was available
Option 2: Manual patch by editing the TFLearn source file locally.
Additional Recommendations: Long-term: TFLearn should migrate to public tf.nest APIs to avoid future breaks.
Debugging Tip: Use tf.version and check TensorFlow’s API docs for deprecated symbols.
Impact: High (breaks all dependent workflows). Priority: Critical for GPU users, moderate for CPU-only.
Let me know if you'd like further details (e.g., stack traces, environment specs)!
Source: tflearn/tflearn