Flake8 correction for _samples_generator.py

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (90312eb) 83.98% compared to head (0569876) 83.98%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #54 +/- ## ======================================= Coverage 83.98% 83.98% ======================================= Files 35 35 Lines 2135 2135 ======================================= Hits 1793 1793 Misses 342 342 ```

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[kachayev]

I thought we have a check in place that prevents us from merging before Flake8 is happy 🤔