list.copy() — Python Technical Interview Questions & Answers

list.copy()

list.copy()

  • list.copy() works on a list. Lists can change. Many methods update the same list (append, pop, sort, insert) instead of returning a new one.
  • list.copy() — output: ['Asha'] then ['Asha', 'Ravi']. copy is a new list.
  • Trap for list.copy(): append([1, 2]) nests a list. extend([1, 2]) adds 1 and 2. sort vs sorted is a viva favourite.
  index →  0       1       2
  list  → [Asha,  Ravi,  Neha]

Technical Interview Tip: In place or new list? Say it first, then one example.

Code Examples for list.copy()

Example

# list.copy()
a = ["Asha"]
b = a.copy()
b.append("Ravi")
print(a)
print(b)

list.copy() — output: ['Asha'] then ['Asha', 'Ravi']. copy is a new list.

How to Explain list.copy() to an Interviewer

Explain list.copy() as if you are teaching a junior — definition, then one tiny script.

list.copy() changes or reads a list. list.copy() — many list methods are in place.

What does the example print, and why?

list

What mistake do freshers make with list.copy()?

list.copy() — sort vs sorted, in place vs new list.