Python software is distributed as a series of libraries that are called within your code to perform certain tasks. There are many different collections, or distributions of Python software. Generally you install a specific distribution of Python and then add additional libraries as you need them. There are also several different versions of Python. Support for Python 2 ended in 2020, so you should use Python>=3! It is import to note that some libraries only work with specific versions of Python.


If you open a terminal on your computer, chances are if you type ‘python’ you will find it is already installed! But it is best-practice to create separate environments or ‘virtual environments’ to not interfere with existing installations. You can use conda for this.

Installing a specific Python version#

We will be using Python 3 during the week. You can create environments with different versions of Python using the following commands:

conda create --name py39 python=3.9

To use Python 3.9:

conda activate py39

To check if you have the correct version activated

which python
python --version

If you are already familiar with Python 2.7, you can take a look at the syntax differences here, but the main point to remember is to put the print statements in parentheses:

print('Hello World!')