Python Collections

Type	Ordered	Mutable	Duplicates	Syntax
list	Yes	Yes	Yes	`[1, 2, 3]`
tuple	Yes	No	Yes	`(1, 2, 3)`
set	No	Yes	No	`{1, 2, 3}`
dict	Yes (3.7+)	Yes	Keys: no	`{"k": "v"}`

List

Positive and negative indexing of a Python list (or string)

Python

nums = [5, 2, 9, 1]
nums.append(7)
nums.sort()
print(nums, nums[0], nums[-1], nums[1:3])

[1, 2, 5, 7, 9] 1 9 [2, 5]

Python

squares = [x * x for x in range(1, 11) if x % 2 == 0]
print(squares)

[4, 16, 36, 64, 100]

Python

a = {1, 2, 3, 4}
b = {3, 4, 5}
print(a | b, a & b, a - b)

{1, 2, 3, 4, 5} {3, 4} {1, 2}

Python

student = {"name": "Meera", "roll": 12}
student["cgpa"] = 9.1
for key, value in student.items():
    print(key, "->", value)

name -> Meera roll -> 12 cgpa -> 9.1

Which collection is immutable?

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