1import tkinter as tk
2from tkinter import messagebox
3 
4def calculate():
5    try:
6        bill = float(bill_e.get())
7        pct = float(pct_e.get())
8        people = int(ppl_e.get())
9    except ValueError:
10        messagebox.showerror("Oops", "Please enter numbers only")
11        return
12    tip = bill * pct / 100
13    result.config(text=f"Tip: Rs {tip:.2f}\nTotal: Rs {bill + tip:.2f}\nEach pays: Rs {(bill + tip) / people:.2f}")
14 
15root = tk.Tk()
16root.title("Tip Calculator")
17for r, text in enumerate(["Bill (Rs)", "Tip %", "People"]):
18    tk.Label(root, text=text).grid(row=r, column=0, sticky="w", padx=8, pady=4)
19bill_e, pct_e, ppl_e = tk.Entry(root), tk.Entry(root), tk.Entry(root)
20for r, e in enumerate([bill_e, pct_e, ppl_e]):
21    e.grid(row=r, column=1, padx=8)
22pct_e.insert(0, "10")
23ppl_e.insert(0, "1")
24tk.Button(root, text="Calculate", command=calculate).grid(row=3, column=0, columnspan=2, pady=6)
25def clear():
26    for e in (bill_e, pct_e, ppl_e):
27        e.delete(0, tk.END)
28    result.config(text="")
29 
30tk.Button(root, text="Clear", command=clear).grid(row=5, column=0, columnspan=2)
31root.bind("<Return>", lambda event: calculate())
32result = tk.Label(root, text="", justify="left")
33result.grid(row=4, column=0, columnspan=2)
34root.mainloop()

1import tkinter as tk
2 
3attempts = 0
4 
5def login():
6    global attempts
7    if user.get().strip().lower() == "admin" and pwd.get() == "Ranchi@123":
8        msg.config(text="Login successful! Opening dashboard...", fg="green")
9        return
10    attempts += 1
11    if attempts >= 3:
12        msg.config(text="Too many attempts. Locked.", fg="red")
13        btn.config(state="disabled")
14    else:
15        msg.config(text=f"Wrong username or password ({3 - attempts} left)", fg="red")
16 
17root = tk.Tk()
18root.title("Staff Login")
19tk.Label(root, text="Username").grid(row=0, column=0, padx=8, pady=6)
20tk.Label(root, text="Password").grid(row=1, column=0, padx=8)
21user = tk.Entry(root)
22pwd = tk.Entry(root, show="*")
23user.grid(row=0, column=1, padx=8)
24pwd.grid(row=1, column=1, padx=8)
25btn = tk.Button(root, text="Login", command=login)
26btn.grid(row=2, column=0, columnspan=2, pady=8)
27msg = tk.Label(root, text="")
28msg.grid(row=3, column=0, columnspan=2)
29root.mainloop()

1import tkinter as tk
2import time
3 
4running = False
5start = 0.0
6elapsed = 0.0
7 
8def tick():
9    if running:
10        shown = elapsed + (time.time() - start)
11        label.config(text=f"{shown:.1f} s")
12        root.after(100, tick)          # call again in 100 ms
13 
14def toggle():
15    global running, start, elapsed
16    if running:
17        elapsed += time.time() - start
18        running = False
19        btn.config(text="Start")
20    else:
21        start = time.time()
22        running = True
23        btn.config(text="Stop")
24        tick()
25 
26def reset():
27    global running, elapsed
28    running, elapsed = False, 0.0
29    label.config(text="0.0 s")
30    btn.config(text="Start")
31 
32root = tk.Tk()
33root.title("Exam Stopwatch")
34label = tk.Label(root, text="0.0 s", font=("Consolas", 40))
35label.pack(padx=20, pady=10)
36btn = tk.Button(root, text="Start", width=8, command=toggle)
37btn.pack(side="left", padx=20, pady=10)
38tk.Button(root, text="Reset", width=8, command=reset).pack(side="right", padx=20)
39root.mainloop()

1from PIL import Image, ImageDraw, ImageFont
2 
3def font(size, bold=False):
4    for name in (["arialbd.ttf", "DejaVuSans-Bold.ttf"] if bold else ["arial.ttf", "DejaVuSans.ttf"]):
5        try:
6            return ImageFont.truetype(name, size)
7        except OSError:
8            pass
9    return ImageFont.load_default()
10 
11def certificate(name, course, grade, filename):
12    img = Image.new("RGB", (900, 560), "#fffdf5")
13    d = ImageDraw.Draw(img)
14    d.rectangle([15, 15, 885, 545], outline="#b07d00", width=8)
15    d.rectangle([32, 32, 868, 528], outline="#3776ab", width=2)
16    d.text((450, 95), "BRAINBIT INFOTECH PVT LTD, RANCHI", fill="#3776ab", font=font(30, True), anchor="mm")
17    d.text((450, 165), "Certificate of Completion", fill="#0b1f3a", font=font(44, True), anchor="mm")
18    d.text((450, 235), "This is to certify that", fill="#5b6577", font=font(22), anchor="mm")
19    d.text((450, 295), name, fill="#c92a2a", font=font(48, True), anchor="mm")
20    d.text((450, 365), f"has completed the {course} course with grade {grade}", fill="#0b1f3a", font=font(24), anchor="mm")
21    d.text((450, 470), "Director                                   08 October 2026", fill="#5b6577", font=font(20), anchor="mm")
22    img.save(filename)
23 
24import csv
25from pathlib import Path
26 
27out = Path("certificates")
28out.mkdir(exist_ok=True)
29count = 0
30with open("batch.csv", encoding="utf-8") as f:
31    for row in csv.DictReader(f):
32        path = out / f"roll_{int(row['roll']):02d}.png"
33        certificate(row["name"], row["course"], row["grade"], path)
34        count += 1
35        print("Saved", path)
36print(count, "certificates ready to print!")

1from pathlib import Path
2from openpyxl import Workbook, load_workbook
3 
4mapping = {"IMG_20260915_101233.jpg": 7, "IMG_20260915_101245.jpg": 12, "IMG_20260916_083010.jpg": 3}
5folder = Path("photos")
6wb = Workbook()
7ws = wb.active
8ws.append(["Old name", "New name"])
9for old, roll in mapping.items():
10    src = folder / old
11    if src.exists():
12        dst = folder / f"roll_{roll:02d}.jpg"
13        src.rename(dst)
14        ws.append([old, dst.name])
15wb.save("rename_log.xlsx")
16 
17for row in load_workbook("rename_log.xlsx").active.iter_rows(values_only=True):
18    print(f"{row[0]:<26} {row[1]}")
19print("Folder now:", sorted(p.name for p in folder.iterdir()))

1"""fees.py - fee rules for BrainBit Infotech Pvt Ltd."""
2from datetime import date
3 
4MONTHLY_FEE: int = 1500
5LATE_FEE_PER_DAY: int = 20
6SIBLING_DISCOUNT: float = 0.10
7 
8 
9def late_fee(days_late: int) -> int:
10    """Late fee for paying after the due date."""
11    return max(0, days_late) * LATE_FEE_PER_DAY
12 
13 
14def fee_due(months: int, has_sibling: bool = False) -> float:
15    """Fee for a number of months, with sibling discount."""
16    fee = months * MONTHLY_FEE
17    return fee * (1 - SIBLING_DISCOUNT) if has_sibling else float(fee)
18 
19 
20def days_between(start: date, end: date) -> int:
21    """Whole days from start to end."""
22    return (end - start).days
23 
24 
25def main() -> None:
26    late = days_between(date(2026, 10, 10), date(2026, 10, 18))
27    total = fee_due(3, has_sibling=True) + late_fee(late)
28    print(f"3 months with sibling discount + {late} days late = Rs {total:,.2f}")
29 
30 
31if __name__ == "__main__":
32    main()

1import pytest
2pytest.main(["-q", "-p", "no:cacheprovider", "test_calc.py"])

1import logging
2logging.basicConfig(filename="atm.log", level=logging.INFO, format="%(levelname)-7s %(message)s")
3log = logging.getLogger("atm")
4 
5accounts = {"XX4521": 8000, "XX7730": 1200}
6 
7def withdraw(acc: str, amount: int) -> None:
8    try:
9        bal = accounts[acc]
10        if amount > bal:
11            log.warning("%s refused: balance %s < %s", acc, bal, amount)
12            return
13        accounts[acc] = bal - amount
14        log.info("%s withdrew %s, balance %s", acc, amount, accounts[acc])
15    except KeyError:
16        log.exception("unknown account %s", acc)
17 
18for acc, amt in [("XX4521", 2000), ("XX7730", 5000), ("XX0000", 100), ("XX4521", 500)]:
19    withdraw(acc, amt)
20print(open("atm.log").read())

1PASS_MARK = 33
2STUDENTS = [("Aman", 78, 85), ("Riya", 25, 40), ("Om", 90, 95)]
3 
4 
5def average(*marks: int) -> float:
6    return sum(marks) / len(marks)
7 
8 
9def grade(avg: float) -> str:
10    if avg >= 90:
11        return "A+"
12    if avg >= 75:
13        return "A"
14    if avg >= PASS_MARK:
15        return "PASS"
16    return "FAIL"
17 
18 
19for name, maths, science in STUDENTS:
20    avg = average(maths, science)
21    print(f"{name} {avg} {grade(avg)}")

1from pathlib import Path
2 
3def scaffold(name: str) -> Path:
4    root = Path(name)
5    files = {
6        f"{name}/__init__.py": "",
7        f"{name}/utils.py": 'def hello() -> str:\n    return "hello"\n',
8        "tests/test_utils.py": f"from {name}.utils import hello\n\ndef test_hello():\n    assert hello() == 'hello'\n",
9        "main.py": f"from {name}.utils import hello\nprint(hello())\n",
10        "requirements.txt": "pytest\n",
11        "README.md": f"# {name}\n\npython -m venv .venv\npip install -r requirements.txt\npython main.py\n",
12        ".gitignore": ".venv/\n__pycache__/\n*.log\n.env\n",
13    }
14    for rel, text in files.items():
15        p = root / rel
16        p.parent.mkdir(parents=True, exist_ok=True)
17        p.write_text(text)
18    return root
19 
20def tree(p: Path, indent: str = "") -> None:
21    for child in sorted(p.iterdir(), key=lambda c: (c.is_file(), c.name)):
22        print(indent + ("|-- " if indent else "") + child.name + ("/" if child.is_dir() else ""))
23        if child.is_dir():
24            tree(child, indent + "    ")
25 
26project = scaffold("fee_app")
27print("fee_app/")
28tree(project, "    ")

1import csv
2 
3SUBJECTS = ["maths", "science", "english"]
4 
5class Student:
6    def __init__(self, roll, name, marks):
7        self.roll, self.name, self.marks = int(roll), name, {s: int(marks[s]) for s in SUBJECTS}
8    def percent(self):
9        return sum(self.marks.values()) / len(SUBJECTS)
10    def grade(self):
11        p = self.percent()
12        return "A+" if p >= 90 else "A" if p >= 75 else "B" if p >= 60 else "C" if p >= 33 else "F"
13 
14def load(path="students.csv"):
15    with open(path, encoding="utf-8") as f:
16        return [Student(r["roll"], r["name"], r) for r in csv.DictReader(f)]
17 
18def save(students, path="students.csv"):
19    with open(path, "w", newline="", encoding="utf-8") as f:
20        w = csv.writer(f)
21        w.writerow(["roll", "name"] + SUBJECTS)
22        for s in students:
23            w.writerow([s.roll, s.name] + [s.marks[x] for x in SUBJECTS])
24 
25def ask_mark(subject):
26    while True:
27        try:
28            m = int(input(f"  {subject} marks: "))
29            if 0 <= m <= 100:
30                return m
31        except ValueError:
32            pass
33        print("  enter 0-100")
34 
35students = load()
36print(f"Loaded {len(students)} students")
37while True:
38    ch = input("\n1 Add  2 Rank list  3 Topper  4 Export & exit: ")
39    if ch == "1":
40        name = input("  Name: ").strip().title()
41        roll = max(s.roll for s in students) + 1
42        students.append(Student(roll, name, {s: ask_mark(s) for s in SUBJECTS}))
43        print(f"  Added roll {roll}")
44    elif ch == "2":
45        for i, s in enumerate(sorted(students, key=lambda s: -s.percent()), 1):
46            print(f"  {i}. {s.name:<13} {s.percent():5.1f}%  {s.grade()}")
47    elif ch == "3":
48        t = max(students, key=lambda s: s.percent())
49        print(f"  Topper: {t.name} ({t.percent():.1f}%)")
50        print("  Subject averages:", {x: round(sum(s.marks[x] for s in students) / len(students), 1) for x in SUBJECTS})
51    elif ch == "4":
52        save(students)
53        with open("report.csv", "w", newline="") as f:
54            w = csv.writer(f)
55            w.writerow(["roll", "name", "percent", "grade"])
56            for s in students:
57                w.writerow([s.roll, s.name, round(s.percent(), 1), s.grade()])
58        print("  Saved students.csv and report.csv. Bye!")
59        break