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LESSON 11
PAGE 2 / 5
Loops - Introduction
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Revisiting Turtle!

Do you remember the program that drew a square in [Lesson 6]?

Instead of writing the sequence 4 times, we can use the for statement. Analyze the example below:
Editor - lesson_11.py
       
Graphic Mode in Python done
Console/Output done
HOW DO WE READ THIS?

For each element in the list, we will draw a side with the color specified by that element!

Python, essentially, does this: the list has 4 elements, so for each one, it executes the set of subordinate instructions! At each step, the variable color holds the current element, meaning the drawing color that we set as an argument for the color() method.

Python is super cool!

It gives us the ability to iterate (that's the name of the operation) within a data collection - in our case, a list that simply holds four colors. So, let's read it again:

for each element of the data collection, perform the following...

Unlike other programming languages, Python allows for a for loop that is natural and close to everyday speech.

Pay attention to indentation, okay?

The set of commands is subordinate to the for statement, so each one must be indented by exactly 4 characters because they all form 3 lines of a compound statement, in this case, a sequential (linear) one!
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