# An example for basic string formatting.
world = "world"
print("Hello, %s!" % world)
print("Hello, {}!".format(world))
print(f"Hello, {world}!")

Hello, world!
Hello, world!
Hello, world!

# An example for string formatting with static precision.
pi = 3.141592653589793
print("The value of pi is approximately %.2f." % pi)
print("The value of pi is approximately {:.2f}.".format(pi))
print(f"The value of pi is approximately {pi:.2f}.")

The value of pi is approximately 3.14.
The value of pi is approximately 3.14.
The value of pi is approximately 3.14.

# Another example for string formatting with dynamic precision.
pi = 3.141592653589793
demical_places = 2
print("The value of pi is approximately %.*f." % (demical_places, pi))
print("The value of pi is approximately {:.{}f}.".format(pi, demical_places))
print(f"The value of pi is approximately {pi:.{demical_places}f}.")

The value of pi is approximately 3.14.
The value of pi is approximately 3.14.
The value of pi is approximately 3.14.

try:
    1 / 0
except ZeroDivisionError as e:
    print(e)


import sys

try:
    1 / 0
except ZeroDivisionError:
    exc_type, exc_value, exc_traceback = sys.exc_info()
    print(exc_value)

division by zero
division by zero

for i in range(5):
    if i == 3:
        break
else:
    print("Loop completed without break!")  # Won't execute because of the break.

n = 0
while n < 3:
    if n == 2:
        break
    n += 1
else:
    print("While loop completed without break!")  # Won't execute.

string = "Hello, " "World!"

message = (
    "This is a very long string "
    "split across multiple lines "
    "but still concatenated implicitly."
)

print(string)
print(message)

Hello, World!
This is a very long string split across multiple lines but still concatenated implicitly.

print(1and 0)
print(1or 0)
print(1if 1else 0)

0
1
1

<>:2: SyntaxWarning: invalid decimal literal
<>:3: SyntaxWarning: invalid decimal literal
<>:3: SyntaxWarning: invalid decimal literal
<>:1: SyntaxWarning: invalid decimal literal
<>:2: SyntaxWarning: invalid decimal literal
<>:3: SyntaxWarning: invalid decimal literal
<>:3: SyntaxWarning: invalid decimal literal
C:\Users\bcw\AppData\Local\Temp\ipykernel_43324\2190328982.py:1: SyntaxWarning: invalid decimal literal
  print(1and 0)
C:\Users\bcw\AppData\Local\Temp\ipykernel_43324\2190328982.py:2: SyntaxWarning: invalid decimal literal
  print(1or 0)
C:\Users\bcw\AppData\Local\Temp\ipykernel_43324\2190328982.py:3: SyntaxWarning: invalid decimal literal
  print(1if 1else 0)
C:\Users\bcw\AppData\Local\Temp\ipykernel_43324\2190328982.py:3: SyntaxWarning: invalid decimal literal
  print(1if 1else 0)

class DefaultDict(dict):
    def __missing__(self, key):
        return f"Key '{key}' is missing!"

d = DefaultDict(a=1)
print(d['a'])  # Output: 1
print(d['b'])  # Output: Key 'b' is missing!

1
Key 'b' is missing!

s = slice(1, 5, 2)  # Equivalent to [1:5:2]
lst = [0, 1, 2, 3, 4, 5]
print(lst[s])  # Output: [1, 3]

[1, 3]

from contextlib import contextmanager

# Defining two custom context managers using the contextmanager decorator
@contextmanager
def first_context():
    print("Entering the first context")
    yield
    print("Exiting the first context")

@contextmanager
def second_context():
    print("Entering the second context")
    yield
    print("Exiting the second context")

# Using both context managers in a single `with` statement
with first_context(), second_context():
    print("Inside both contexts")

Entering the first context
Entering the second context
Inside both contexts
Exiting the second context
Exiting the first context

print(...)

Ellipsis

words = ['apple', 'banana', 'cherry']
longest_word = max(words, key=len)
print(longest_word)

banana

lst = [1, 2, 3, 4, 5]
del lst[1:4]
print(lst)

[1, 5]

x = y = 5
print(1 < x <= y < 10)

True

table = str.maketrans("abc", "123")
print("abcde".translate(table))

123de

class MyNumber:
    def __init__(self, value):
        self.value = value

    def __pos__(self):
        return abs(self.value)

n = MyNumber(-5)
print(+n)

5

def subgen():
    yield 1
    yield 2

def main_gen():
    yield from subgen()
    yield 3

print(list(main_gen()))

[1, 2, 3]