Python Cheatsheet

Downloading and installing Python

Python is a high-level interpreted programming language that is supported by most major [[ os|operating systems ]]. All CIE courses require that students complete their work using a version of Python3 (at the time of writing 3.10 is the most up to date release).

Python can be downloaded and installed from the official Python website.

If for any reason you are not able to install Python on your device, there are browser based versions you can use such as trinket.io

Creating a variable

Getting data from the user

Outputting data to the user

Making choices

Counting loop

Pre-condition loop

Post-condition loop

Most programming languages include a type of loop known as a do...while loop. These loops are similar to while loops but have one major difference, the condition is checked at the end of the loop rather than at the beginning of the loop. By making use of this type of loop, the code within the loop is guaranteed to run at least once.

Python does not provide support for these types of loops. In order to build a post-condition loop in python, you need to combine a while loop with an if statement and a break statement.

The following code sample asks a user to enter a new password, the program will only let the user continue if their password is at least 8 characters long

while True: # This sets up an infinite loop
  password = input("Please enter a new password": )

  if len(password) >= 8:
    print("Password updated")
    break # This statement stops the loop from repeating
  else:
    print("Passwords must be at least 8 characters long")

Working with lists