Python错误“int”对象没有属性“shape”

使用下面的示例, sklearn 使用Python 3.5:

from sklearn import tree
features = [[140,1], [130,1], [150,0], [155,0]]
labels = [0,0,1,1]

clf = tree.DecisionTreeClassifier()
clf.fit(features, labels)
print(clf.predict(155,0))

我得到了错误后的错误。我不明白为什么我收到这个错误,有人能解释一下吗?

Traceback (most recent call last):
  File "ml.py", line 7, in <module>
    print(clf.predict(155,0))
  File "/Users/user/Documents/hello/env/lib/python3.5/site-packages/sklearn/tree/tree.py", line 404, in predict
    X = self._validate_X_predict(X, check_input)
  File "/Users/user/Documents/hello/env/lib/python3.5/site-packages/sklearn/tree/tree.py", line 371, in _validate_X_predict
    n_features = X.shape[1]
AttributeError: 'int' object has no attribute 'shape'