fit()缺少1个必需的位置参数:“ y”

from sklearn.model_selection import train_test_split
mesg_train, mesg_test, label_train, label_test = train_test_split( messages['message'], messages['label'], test_size=0.33)
from sklearn.pipeline import Pipeline
pipeline=Pipeline([('bow',CountVectorizer(analyzer=text_process)),('tfidf',TfidfTransformer()),('classifier',MultinomialNB)])
pipeline.fit(mesg_train,label_train)

TypeError                                 Traceback (most recent call last)
<ipython-input-112-2ebb345a86aa> in <module>
----> 1 pipeline.fit(mesg_train,label_train)

~\Anaconda3\lib\site-packages\sklearn\pipeline.py in fit(self, X, y, **fit_params)
    352                                  self._log_message(len(self.steps) - 1)):
    353             if self._final_estimator != 'passthrough':
--> 354                 self._final_estimator.fit(Xt, y, **fit_params)
    355         return self
    356 

TypeError: fit() missing 1 required positional argument: 'y'

尽管给出了y参数,但仍然出现此错误