Python basics: print, variable, f-string, list and loop

Beginner level · lesson 2 · about 14 min

Python runs code from top to bottom, line by line. To show a result on the screen you use print(); text (a string) is written in quotation marks.

print("Salom, dunyo!")

OutputSalom, dunyo!

A variable is a name attached to a value: the = sign attaches the value to the name. An f-string (an f before the quotation marks) puts the value of a variable into the text through {}. This is how request texts for a model are prepared later.

model = "Mini"
versiya = 2
print(f"Men {model} v{versiya} bilan ishlayapman.")

OutputMen Mini v2 bilan ishlayapman.

A list holds several values in square brackets; items are numbered from 0. A for loop repeats the same action for every item in the list. The lines inside a loop are indented by 4 spaces: in Python this matters.

mavzular = ["token", "prompt", "agent"]
print(mavzular[0])
for mavzu in mavzular:
    print(f"Mavzu: {mavzu}")

Outputtoken
Mavzu: token
Mavzu: prompt
Mavzu: agent

Remember

print() shows a result on the screen.
f-string: f"... {variable} ...".
List: [...]; loop: for x in items: with 4 spaces inside.

Exercise

If ism = "Ali", what does print(f"Salom, {ism}") print?

Answer and explanation

Salom, {ism}in an f-string the name in curly braces is replaced by its value.
Salom, Ali (correct answer)the f-string puts the variable’s value in place of {ism}.
ismthat is the variable’s name, not its value.

Code exercises

Print the word salom (Uzbek for “hello”) on the screen.
Hint: Write the text in quotation marks inside print(...).
Put “Ali” into the variable ism and, using an f-string, print Salom, Ali!.
Hint: Write f before the quotation marks and put the variable in curly braces: {ism}.
Print every word in the list sozlar in capital letters, each on its own line.
Hint: After for soz in sozlar: write the print command indented by 4 spaces. A string has the .upper() method for capital letters.

Do the exercise in the app.

Practical task

Put 3 words you like into a list and, using a loop, print each one inside a sentence with an f-string. Try the code in the exercise editor.

I made a list
I wrote a loop
I looked at the result and understood it

Glossary

Open in the app

Interactive mode: search, progress and Python exercises.