Python Cheatsheet

List comprehension

squares = [x**2 for x in range(10)]
evens = [x for x in range(10) if x % 2 == 0]

Dict

d = {"a": 1, "b": 2}
d.get("c", 0)              # Safe get
{k: v for k, v in d.items() if v > 1}

Lambda

add = lambda a, b: a + b
sorted(list, key=lambda x: x[1])

File I/O

with open("file.txt", "r") as f:
    content = f.read()

Error handling

try:
    risky()
except ValueError as e:
    print(e)
finally:
    cleanup()

Type hints

def greet(name: str) -> str:
    return f"Hello {name}"