3-3.Bi-LSTM may have wrong padding

In line 16 you use
` input = input + [0] * (max_len - len(input))`
the padding, you use 0, which means the first word 'Lorem'.
but it is not the right choose.
I think you can change like that
```
# word_dict = {w: i for i, w in enumerate(list(set(sentence.split())))}
# number_dict = {i: w for i, w in enumerate(list(set(sentence.split())))}
word_dict = {w: i for i, w in enumerate(['PAD']+list(set(sentence.split())))}
number_dict = {i: w for i, w in enumerate(['PAD']+list(set(sentence.split())))}
```

Open the 3-3.Bi-LSTM entry and inspect line 16, where padding is appended to inputs. Verify that the padding index is distinct from the first word and is used consistently; the issue is done when padded inputs no longer map to “Lorem” and the example still runs.

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