Handle wrong lines in the dictionary (empty line or unknown symbols)

[mimipaskova]

I had some error with dictionaries which I generated. Some of the words/symbols cannot be read from python and there is an error in line 60 in word_translation - ValueError: not enough values to unpack (expected 2, got 0)
I manage to check this in if and to show and ignore these words.

My case is supervised with dico-train default with my custom dictionaries.

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[glample]

Thank you!