def term_count_buckets(self):
buckets = {}<EOL>for term, count in self.term_counts().items():<EOL><INDENT>if count in buckets: buckets[count].append(term)<EOL>else: buckets[count] = [term]<EOL><DEDENT>return buckets<EOL>
Returns:
    dict: A dictionary that maps occurrence counts to the terms that
    appear that many times in the text.