update scikit learn in anaconda code example

Example 1: conda install sklearn 0.20

conda install scikit-learn=0.20

Example 2: conda install sklearn

python3 -m venv sklearn-venvpython -m venv sklearn-venvpython -m venv sklearn-venvsource sklearn-venv/bin/activatesource sklearn-venv/bin/activatesklearn-venv\Scripts\activatepip install -U scikit-learnpip install -U scikit-learnpip install -U scikit-learnpip3 install -U scikit-learnconda create -n sklearn-envconda activate sklearn-envconda install scikit-learn