Read the Error: Fix Five Broken Scripts from Their Tracebacks

The coffee machine's counter should say how many cups are left. Run cups.py, and start reading from the last line:

TypeError: can only concatenate str (not "int") to str

A TypeError means an operation got the wrong type of thing. + between two strings joins them ("concatenate" means join); between two numbers it adds. Between a string and a number Python won't guess which you meant, so it stops. The line above the message shows where: "Cups left: " + cups_left, where cups_left is the number 24.

Make it print:

Cups left: 24

An f-string is the usual fix, f"Cups left: {cups_left}", because it turns whatever is in the braces into text. str(cups_left) turns a number into text too.

# The coffee machine's counter.
cups_left = 24
print("Cups left: " + cups_left)

Quick one. Run hours.py:

  File "/home/labuser/hours.py", line 3
    closes = "18:00"
IndentationError: unexpected indent

Python reads the spaces at the start of a line. A line that starts further in than the one before tells Python "this belongs inside the line above", and here there's nothing for it to belong to. From Level 2 you'll indent lines on purpose, under an if. For now, every line starts at the left edge.

Fix it so the sign prints:

Open 7:30 to 18:00

# The opening-hours sign.
opens = "7:30"
 closes = "18:00"
print(f"Open {opens} to {closes}")

The last script prints the labels that go on cups. Sam left a note taped to the printer:

Name in capitals, so we can read it across the counter. Size with a capital first letter. Sam Rivera's two large flat whites: SAM RIVERA | Large x 2

Run labels.py. It crashes with an AttributeError: the script asked a string for a method it doesn't have. Read the last line, Python suggests the name it meant, and fix it.

Then run it again. It runs this time and prints a label, but compare it with Sam's note. This second bug is the quiet kind: no traceback, just the wrong output. Python stops at the first error it meets, and a script that runs isn't the same as a script that's right. Make the label match the note:

SAM RIVERA | Large x 2

.upper() puts every letter in capitals, .title() gives each word a capital first letter and .capitalize() gives only the first letter of the text one. That's the last broken script: the café opens on time. Opening Morning is next, Level 1's boss.

# The cup-label printer: a name and a size on every cup.
name = "  sam rivera"
size = "large"
cups = 2

label = f"{name.strip().titel()} | {size.upper()} x {cups}"
print(label)