most_common() not fully utilized?

[yuhsianglin]

In preprocess.py, in build_vocab(), there is a line of code:
all_words = collections.Counter(all_text).most_common()
It seems that at this moment the "most_common()" part is not really utilized. But could potentially pick the most common N words here.

[yuhsianglin]

Note that most_common() cast the dictionary into list.