Python values and variables
01Store and inspect simple data.
Preparing the interface
WaypointPrepared demo project
Read a complete Waypoint learning loop. Nothing here is saved or sent to AI.
Python foundations · prepared project
2 of 8 topics completedBuild confidence with Python functions
Learning goal
Write small, reusable Python functions that accept inputs, return useful values, and handle a simple edge case.
Learner profile
- Starting point
- New to Python; comfortable with variables and lists
- Time available
- 4 sessions per week · 30 minutes
- Preferred practice
- Short coding tasks with clear feedback
Your learning path
One topic opens after the required practice has been validated.
Functions with inputs and returns
02Turn repeated steps into a clear function.
Decisions with if statements
03Choose a result for an edge case.
Working with lists
04Collect and transform related values.
Loops for repeated work
05Process a list one item at a time.
Dictionaries for named data
06Model a small record.
Reading and writing files
07Persist a simple result.
A small command-line tool
08Combine the pieces in one useful script.
Current lesson · topic 02
Functions with inputs and returns
A function gives a repeated step a name. Inputs make it flexible; a return value makes its result available to the next line of your program.
By the end of this lesson, you can
- define a function with a descriptive name
- accept a value through a parameter
- return a result instead of only printing it
Inputs are parameters
Parameters are names inside the function definition. When you call the function, you provide the real value as an argument. This lets one function work with many values.
Returns keep the result usable
print() shows something to a person, while return sends a value back to the code that called the function. A returned value can be stored, compared, or passed into another function.
A small reusable formatter
This function accepts a name and returns a greeting. The caller decides what to do with the returned text.
def greeting(name: str) -> str:
return f"Hello, {name}!"
message = greeting("Maya")
print(message)Quick check
Why is return more useful than print() when another part of your program needs the value?
Submitted practice · attempt 1
Write a safe total function
Create a function named total_price that accepts price and quantity. Return price × quantity for a positive quantity. If quantity is zero or less, return 0.
What the solution needs
- Use the exact function name total_price.
- Accept price and quantity as parameters.
- Use return for both outcomes.
- Handle zero and negative quantities.
Submitted answer
Submitted · evaluated in this prepared example
def total_price(price: float, quantity: int) -> float:
if quantity <= 0:
return 0
return price * quantityRubric
Function structure
25 / 25Clear name and both required parameters.
Correct calculation
30 / 30Returns price × quantity for a positive quantity.
Edge case
25 / 25Zero and negative quantities return 0.
Readable solution
12 / 20Readable and direct; a short docstring would improve it.
Evaluation complete
Practice passed
92 / 100
Passed · required practice validated
Feedback
- Your parameters make the function reusable instead of hard-coding a value.
- The guard clause handles the requested edge case before the calculation runs.
- Next time, add a brief docstring to explain the unit of price.
Next topic unlocked
Topic 03 · Decisions with if statements is now available because this practice passed validation.