Python 101

Python is a powerful, easy to user, object oriented programming language.

History of Python

It’s performant meaning it runs on all operating systems and it’s extremely versatile.

Python’s versatility; scripts & programs, web development, data science

  • Command line calculators
  • UI to create desktop apps
  • Server side language
  • Full stack apps or REST APIs
  • Frameworks like Django and Flask
  • Gather, import and clean data
  • Machine Learning

Python has a clean and simple syntax. Has a “batteries included” approach and offers great documentation.

Python embraces objects, classes, inheritance and allows you to easily work with complex data structures.

Getting Started

Download package

Install package

Launch terminal then run: “python”.

Now you’re in the terminal REPL.

In terminal run: “2+2”

run: user_name = input(‘Please enter your name: ‘) 

To exit the REPL run “exit()”.

Read From A File

Create a directory in an easily accessible folder. Create a file called

cd ~/Python
print "My Python Script"

In terminal run “python”.

Your First Function

Add this to your, and run it.

def greet(name, age):
print('My name is ' + name + ', I am ' + age)

greet(name='Justin', age='26')

Your output should look like this:

List Comprehension

List comprehensions provide a concise way to create lists.

It consists of brackets containing an expression followed by a for clause, then zero or more for or if clauses.

The expressions can be anything, meaning you can put in all kinds of objects in lists.

The result will be a new list resulting from evaluating the expression in the context of the for and if clauses which follow it.

The list comprehension always returns a result list.

Turn the following code:

new_list = []
for i in old_list:
    if filter(i):

Into this with list comprehension:

new_list = [expression(i) for i in old_list if filter(i)]

Dictionary Comprehension

stats = [('age', 29), ('weight', 72), ('height', 178)]
dict_stats = {key: value for (key, value) in stats}