Execute script in IDLE with parameters

[buran]

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no, you should add

import sys
sys.argv = [sys.argv[0], '--dataset', '../datasets/animals']

The first element of sys.argv is always the script itself
the best would be to add the import statement at the top of the file and the other line as first line in if __name__ == '__main__': block. Note that this may vary little depending how your knn.py looks like.