usercode.py

"""
Write out the code:
    def level_1():
        return 'Hello, world!'
The `def hello_world()`, a function definition, tells the computer that all lines of code indented under it are instructions describing how to run the function `level_1()`. The `return 'Hello, world!'` tells the computer to give the text `'Hello, world!'` to the program that is tasked with running this code. This text is usually called a string.
Make sure to get rid of the `pass` statement in your code.
"""
def level_1():
    pass

"""
Now it's time for variables! A variable in Python is a changeable value stored under a particular name. For example, the variable `foo` might be storing the string `'bar'`. We don't have to know what each variable is holding; we can use variable names *without* quotes in place of any string, and the computer will automatically replace the variable name with whatever is stored inside that variable.
You can accept input as a variable (name the variable whatever you want) by putting a variable name inside the parentheses of the function definition.
"""
def level_2(arg):
    pass

"""Alright, integers. Integers are numbers, positive, negative, or zero, with no fractional part. In Python, integers are notated by just the number itself; in other words, you don't need quotes or anything, unlike strings. Just like strings, however, integers can be stored in variables. They can also be operated on. For example, `2 + 3` is actually acceptable Python code that evaluates to `5` (`return 2 + 3` will just return `5`).
"""
def level_3(arg):
    pass

"""Conditionals! Conditionals, or `if` statements, run different code based on whether something is `True` or `False`. `True` and `False` are actually Python keywords. They are called boolean values. A variable can be assigned a boolean value, so `foo = True` is valid code. An `if` statement is written like so:
    if a:
        <Your code here for if `a` is `True`>
    elif !a:
        <Your code here for if `a` is `False`>
    elif b == 'Hello':
        <Your code here for if `b` is `'Hello'`>
    elif b != 'Hello':
        <Your code here for if `b` is *not* `'Hello'`>
    elif c == 4:
        <Your code here for if `c` is `4`>
    elif c > 5:
        <Your code here for if `c` is greater than `5`>
    elif c <= 3:
        <Your code here for if `c` is less than or equal to `3`>
    elif c != 2:
        <Your code here for if `c` is *not* `2`>
    else:
        <Your code here for if none of the above conditions work>
In this example, `a`, `b`, and `c` are variables. You do not have to include all of these components in an `if` statement, so only check for what is necessary.
"""
def level_4(arg):
    pass