fix failure in mlstm introduced by #17

And add a smoke test for graph-based to avoid this in the future

tox.ini

@@ -1,8 +1,9 @@
 [tox]
 minversion = 3.4.0
-envlist = py38
+envlist = py38, py37
 
 [testenv]
 deps = cython
 commands =
-    uuparser --dynet-seed 123456789 --outdir {envtmpdir}/smoketestoutput --trainfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --devfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --testfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu
+    uuparser --dynet-seed 123456789 --epochs 3 --outdir {envtmpdir}/transition-smoketest-output --trainfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --devfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --testfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu
+    uuparser --dynet-seed 123456789 --epochs 3 --graph-based --outdir {envtmpdir}/graph-smoketest-output --trainfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --devfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu --testfile test/fixtures/truncated-sv_talbanken-ud-dev.conllu

uuparser/mstlstm.py

@@ -1,17 +1,19 @@
 from operator import itemgetter
-import time, random, decoder
-from chuliu_edmonds import chuliu_edmonds_one_root
+import time, random
 import numpy as np
-from multilayer_perceptron import biMLP
 from collections import defaultdict
 from copy import deepcopy
 
-from uuparser import utils
+from loguru import logger
+
+from uuparser import utils, decoder
+from uuparser.chuliu_edmonds import chuliu_edmonds_one_root
+from uuparser.multilayer_perceptron import biMLP
 
 class MSTParserLSTM:
     def __init__(self, vocab, options):
         import dynet as dy
-        from feature_extractor import FeatureExtractor
+        from uuparser.feature_extractor import FeatureExtractor
         global dy
         self.model = dy.ParameterCollection()
         self.trainer = dy.AdamTrainer(self.model, alpha=options.learning_rate)