fix python formatting · UW-Madison-DataScience/machine-learning-novice-sklearn@5ab53f9

[image missing alt-text]: fig/penguin_regression_all.png

[image missing alt-text]: fig/regress_penguin_lin.png

[image missing alt-text]: fig/penguin_regression.png

[image missing alt-text]: fig/regression_example.png

[image missing alt-text]: fig/introduction/ML_summary.png

[image missing alt-text]: fig/introduction/sklearn_input.png

[needs HTTPS]: [SciPy (Scientific Python)](http://scipy.org)

[needs HTTPS]: [NumPy (Numerical Python)](http://numpy.org)

[needs HTTPS]: [Scikit-Learn](http://github.com/scikit-learn/scikit-learn)

[image missing alt-text]: fig/introduction/AI_ML_DL_differences.png

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