Summary  
This chapter introduces basic arithmetic operations in Python—addition, subtraction, multiplication, and division—and shows how to use the print() function to display numerical results.

General domain of usage  
Data analysis

Python excels at crunching numbers. It supports various mathematical operations, from basic arithmetic to complex calculations.

Use the `print()` function to display results. Mathematical expressions don’t require quotation marks (`"..."` or `'...'`), unlike text.

# Addition
print(1039 + 948)

# Subtraction
print(10484 - 9274)

# Multiplication
print(116 * 99)

# Division
print(95873 / 472)

import unittest
import importlib
import io
import re
import sys

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)

class TestUserCode(unittest.TestCase):

    def test_addition_operation_present(self):
        """
        Test to ensure the addition operation `2580 + 198` is present.
        """
        with open('user_code.py', 'r') as file:
            user_code_source = file.read()

        addition_check = re.search(r'2580\s*\+\s*198', user_code_source)

        _dynamic_test(
            self,
            addition_check is not None,
            "The addition operation `2580 + 198` is present.",
            "Expected the addition operation `2580 + 198` to be present."
        )

    def test_multiplication_operation_present(self):
        """
        Test to ensure the multiplication operation `23 * 42` is present.
        """
        with open('user_code.py', 'r') as file:
            user_code_source = file.read()

        multiplication_check = re.search(r'23\s*\*\s*42', user_code_source)

        _dynamic_test(
            self,
            multiplication_check is not None,
            "The multiplication operation `23 * 42` is present.",
            "Expected the multiplication operation `23 * 42` to be present."
        )

    def test_division_operation_present(self):
        """
        Test to ensure the division operation `1512 / 27` is present.
        """
        with open('user_code.py', 'r') as file:
            user_code_source = file.read()

        division_check = re.search(r'1512\s*/\s*27', user_code_source)

        _dynamic_test(
            self,
            division_check is not None,
            "The division operation `1512 / 27` is present.",
            "Expected the division operation `1512 / 27` to be present."
        )

    def test_correct_output_printed(self):
        import user_code
        captured_output = io.StringIO()
        sys.stdout = captured_output
        importlib.reload(user_code)
        sys.stdout = sys.__stdout__

        output = captured_output.getvalue().strip().split("\\n") 

        expected_outputs = ["2778", "966", "56.0"]

        for i, expected in enumerate(expected_outputs):
            _dynamic_test(
                self,
                output[i] == expected,
                f'The correct result `{expected}` is printed for operation {i + 1}.',
                f'Expected `{expected}` to be printed, but got `{output[i]}`.'
            )

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

test_main.py

Python is an interpreted high-level general-purpose programming language. Unlike HTML, CSS, and JavaScript, which are primarily used for web development, Python is versatile and can be used in various fields, including software development, data science, and back-end development. In this course, you'll explore the core aspects of Python, and by the end, you'll be crafting your own functions!

Dive into the basics of Python, explore your workspace, and perform simple math operations. Learn how to write readable code using comments and handle both basic and advanced mathematical expressions while displaying your results.

Learn how to store and manage data in Python by working with numbers, text, and variables. Understand how to assign values, follow naming conventions, and explore different data types. Gain hands-on experience with string operations, indexing, slicing, and memory recall techniques to efficiently manipulate text in Python.

Learn how to use comparison and logical operators, work with conditional expressions, and apply membership and type comparisons. Build a strong foundation in writing programs that respond dynamically to different conditions using if/else and if/elif/else structures.

Expand your understanding of data types by learning how to group multiple attributes within a single variable. Explore lists, tuples, and dictionaries to efficiently store and manage structured data, along with essential methods for manipulation and retrieval.

Master the art of writing loops in Python—essential constructs for iterating over lists, tuples, dictionaries, and other data structures. Learn to use while and for loops effectively, explore the range function, and work with nested loops to handle complex iteration patterns.

Explore essential built-in functions in Python and take the next step by creating your own. Learn how to define functions, use conditional logic, modify existing functions, and work with lambda expressions to write efficient, reusable code.

Perform Simple Math in Python

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