
import unittest
import user_code
import ast
import re   
import importlib
import csv
import unittest
import importlib
import io
from contextlib import redirect_stdout

class TestTask(unittest.TestCase):
    def test_average_non_empty_list(self):
        import user_code
        importlib.reload(user_code)
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_average([10, 20, 30, 40, 50])
        output = normalize_text(f.getvalue())
        expected = normalize_text("The average is: 30.0")
        _dynamic_test(
            self,
            expected in output,
            "Correct average printed for non-empty list.",
            f"Expected '{expected}' in output, got '{output}'",
        )

    def test_average_empty_list(self):
        import user_code
        importlib.reload(user_code)
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_average([])
        output = normalize_text(f.getvalue())
        expected = normalize_text("The average is: 0")
        _dynamic_test(
            self,
            expected in output,
            "Correct average printed for empty list.",
            f"Expected '{expected}' in output, got '{output}'",
        )

    def test_average_single_number(self):
        import user_code
        importlib.reload(user_code)
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_average([42])
        output = normalize_text(f.getvalue())
        expected = normalize_text("The average is: 42.0")
        _dynamic_test(
            self,
            expected in output,
            "Correct average printed for single number.",
            f"Expected '{expected}' in output, got '{output}'",
        )

    def test_average_negative_numbers(self):
        import user_code
        importlib.reload(user_code)
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_average([-5, -15, 10])
        output = normalize_text(f.getvalue())
        expected = normalize_text("The average is: -3.3333333333333335")
        _dynamic_test(
            self,
            expected in output,
            "Correct average printed for negative and positive numbers.",
            f"Expected '{expected}' in output, got '{output}'",
        )

def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)

def normalize_text(text):
    text = text.lower()
    text = re.sub(r"\\s{2,}", " ", text)
    text = re.sub(r"\\s*([,:?])\\s*", r"\\1 ", text)
    return text.strip()

def change_var(code: str, var_name: str, value: str) -> str:
    tree = ast.parse(code)
    lines = code.splitlines()
    changed = False
    # Collect all assignment nodes to modify
    assign_nodes = [
        (i, node)
        for i, node in enumerate(tree.body)
        if isinstance(node, ast.Assign)
        and any(isinstance(target, ast.Name) and target.id == var_name for target in node.targets)
    ]

    # If nothing to change, return unmodified code
    if not assign_nodes:
        return code

    # Perform replacements for all matching assignments (from last to first to not break line offsets)
    for i, node in reversed(assign_nodes):
        start_line = node.lineno - 1
        line = lines[start_line]
        indent = ' ' * (len(line) - len(line.lstrip()))
        lines[start_line] = f"{indent}{var_name} = {value}"
        next_line = len(lines)
        for next_node in tree.body[i+1:]:
            if hasattr(next_node, 'lineno'):
                next_line = next_node.lineno - 1
                break
        if next_line > start_line + 1:
            lines[start_line+1:next_line] = []
        changed = True

    return '\\n'.join(lines) if changed else code

if __name__ == "__main__":
    unittest.main()


test_main.py

Learn how to automate everyday and system-related tasks using Python. This beginner-friendly course alternates between conceptual explanations and hands-on tasks, guiding you through practical automation scenarios and essential system operations.

Explore practical automation scenarios using Python, from simple repetitive tasks to essential system operations. Alternate between conceptual learning and hands-on practice.

Challenge: Calculate and Print Averages

Solution