Category Archives: Machine Learning

How to Completely Uninstall Python on macOS


You have an issue with a Python version (e.g. the 3.7 version) and want to install another version (e.g. the 3.6 version). In order to install a fresh version you need to uninstall the current version first.


Assume that the current version is 3.7. Replace 3.7 with another version that you installed.

Follow these 3 steps below.

1. Remove the third-party Python 3.7 framework

sudo rm -rf /Library/Frameworks/Python.framework/Versions/3.7

2. Remove the Python 3.7 applications directory

sudo rm -rf "/Applications/Python 3.7"

3. Remove the symbolic links, in /usr/local/bin, that point to this Python version. Ensure that the links exit using below command

ls -l /usr/local/bin | grep '../Library/Frameworks/Python.framework/Versions/3.7'

then run the following commands to remove all the links:

cd /usr/local/bin/
ls -l /usr/local/bin | grep '../Library/Frameworks/Python.framework/Versions/3.7' | awk '{print $9}' | tr -d @ | xargs rm

Installing a new version:

  1. Download a version from, double click the file and follow the instructions.
  2. Verify installation: python3 –version
  3. Install Homebrew from
  4. Install virtualenv
pip3 install virtualenv
pip3 install virtualenvwrapper

5.  Create and activate a virtual environment

cd /Users/admin/Downloads/training_model/model 
python3 -m virtualenv /Users/admin/Downloads/training_model/model
source bin/activate

Topic 20 – Introduction to Applied Machine Learning

Why do I need to learn about applied machine learning?

Machine learning has solved many important difficult problems recently. A few of them include speech recognition, speech synthesis, image recognition, autonomous driving and chat bots.
Nowadays a key skill of software developer is the ability to use machine learning algorithms solve real-world problems.

What can I do after finishing learning about applied machine learning ?

You will be to create software that could recognize speech, recognize a face, translate text to speech, translate a sentence from English to French, answer a customer’s question.

That sounds useful! What should I do now?

Please attend this free Machine Learning (Coursera) course and audit this Applied Machine Learning in Python (Coursera) course first.

At the same time, please read
– this Aurelien Geron (2019). Hands-On Machine Learning with Scikit-Learn, Keras and TensorFlow. O’Reilly Media book and
– this Brett Lantz (2019). Machine Learning with R – Expert Techniques for Predictive Modeling. Packt Publishing book.

After that please audit these Deep Learning Specialization courses.
At the same time, please read
– this Francois Chollet (2021). Deep Learning with Python. Manning Publications book and
– this Michael Nielsen (2015). Neural Networks and Deep Learning. Determination Press book.

After that please read this Christopher M. Bishop (2006). Pattern Recognition and Machine Learning. Springer book.

After finishing reading these books please click Topic 21 – Introduction to Applied Computer Vision and Natural Language Processing to continue.