error installing scikit learn code example

Example 1: install sklearn

pip install scikit-learn

Example 2: scikit-learn install error

pip install -U scikit-learn

Example 3: scikit-learn install error

sudo pip3 install scikit-learn

Example 4: sklearn version

import nltk
import sklearn

print('The nltk version is {}.'.format(nltk.__version__))
print('The scikit-learn version is {}.'.format(sklearn.__version__))

# The nltk version is 3.0.0.
# The scikit-learn version is 0.15.2.