Python scikit-learnのImportError

$ conda info
--
          conda version : 4.7.10
    conda-build version : 3.18.8
         python version : 3.7.3.final.0

from sklearn.datasets import load_iris
dataset = load_iris()
--

ImportError: DLL load failed: 指定されたプロシージャが見つかりません。

$ pip install -U sklearn

$ pip install -U numpy

$ pip install -U scipy

from sklearn.datasets import load_iris
dataset = load_iris()
print("key of dataset:\n{}".format(dataset.keys()))

--

key of dataset:
dict_keys(['data', 'target', 'target_names', 'DESCR', 'feature_names', 'filename'])