Modules and the standard library: import, math, random, datetime, statistics, os and pip

import math                         # import the whole module
print(math.sqrt(144), math.pi)

from math import ceil, floor        # import specific names
print(ceil(4.1), floor(4.9))

import statistics as st             # alias (short name)
print(st.mean([60, 70, 80]))

# pricing.py
VAT_RATE = 0.16

def add_vat(amount):
    return round(amount * (1 + VAT_RATE), 2)

def format_ksh(amount):
    return f"KSh {amount:,.2f}"

# main.py
from pricing import add_vat, format_ksh
print(format_ksh(add_vat(1000)))    # KSh 1,160.00

def add_vat(amount):
    return round(amount * 1.16, 2)

if __name__ == "__main__":
    # quick tests when running this file directly
    print(add_vat(1000))

import math
print(math.sqrt(2), math.pow(2, 10), math.factorial(5))
print(math.ceil(130 / 33))           # buses needed
print(math.isclose(0.1 + 0.2, 0.3))  # compare floats safely
print(math.gcd(48, 36), math.lcm(4, 6))

import random
random.seed(1)                        # same results every run (useful for testing)
print(random.randint(1, 6))           # dice roll 1-6
print(random.choice(["Nairobi", "Mombasa", "Kisumu"]))
cards = list(range(1, 11))
random.shuffle(cards)
print(cards)
print(random.sample(range(1, 50), 6))   # 6 unique numbers
print(round(random.uniform(1.5, 3.5), 2))

import secrets
code = f"{secrets.randbelow(1_000_000):06d}"
print("6-digit code:", code)
print("Token:", secrets.token_urlsafe(12))

import statistics as st
marks = [78, 45, 90, 66, 85, 66, 52]
print("Mean:", round(st.mean(marks), 1))
print("Median:", st.median(marks))
print("Mode:", st.mode(marks))
print("Std dev:", round(st.stdev(marks), 1))

from datetime import date, datetime, timedelta

today = date(2026, 10, 2)
due = today + timedelta(days=30)
print("Due date:", due, due.strftime("%A %d %B %Y"))

exam = date(2026, 11, 3)
print((exam - today).days, "days to the exam")

dt = datetime(2026, 10, 2, 14, 30)
print(dt.strftime("%d/%m/%Y %H:%M"))
print(datetime.strptime("15/12/2005", "%d/%m/%Y").year)   # parse text into a date
print(dt.isoformat())

from collections import Counter, defaultdict, namedtuple

words = "unga sukari unga maziwa unga sukari".split()
print(Counter(words).most_common(2))

groups = defaultdict(list)
for name, cls in [("Amina", 9), ("Brian", 8), ("Chebet", 9)]:
    groups[cls].append(name)
print(dict(groups))

Point = namedtuple("Point", "lat lon")
nairobi = Point(-1.2921, 36.8219)
print(nairobi.lat, nairobi.lon)

import os, sys
from pathlib import Path

print(os.getcwd())                      # current folder
Path("demo").mkdir(exist_ok=True)
Path("demo/a.txt").write_text("hello", encoding="utf-8")
print(os.listdir("demo"))
print(Path("demo/a.txt").suffix, Path("demo/a.txt").stem)
print(sys.version.split()[0])           # Python version

import json, csv, io

data = {"shop": "Juma Electronics", "items": [{"name": "Speaker", "price": 3500}]}
text = json.dumps(data, indent=2)
print(text)
print(json.loads(text)["items"][0]["price"])

rows = "name,price\nUnga,180\nSugar,150\n"
for row in csv.DictReader(io.StringIO(rows)):
    print(row["name"], int(row["price"]))

import time
start = time.perf_counter()
total = sum(range(1_000_000))
print("Took", round(time.perf_counter() - start, 4), "seconds")

pip install requests        # popular package for web requests
pip install pandas openpyxl # data analysis + Excel files
pip list                    # see installed packages
pip install -r requirements.txt

python -m venv .venv
# Windows:  .venv\Scripts\activate
# Mac/Linux: source .venv/bin/activate
pip install requests
pip freeze > requirements.txt     # record exact versions for others/servers