1. Adding Elements

• append()
• extend()
• insert()

2. Removing Elements

• remove()
• pop()
• clear()

3. Accessing Elements

• index()
• count()

4. Sorting & Reversing

• sort()
• reverse()

5. Copying & Joining

• copy()

6. List Comparison & Operations

• (No direct methods, but ==, +, * are used with lists)

Note:

• These are the built-in methods for lists in Python (as of Python 3.x).
• Some operations (like slicing, concatenation) use syntax rather than methods.

Python List copy() Method with Examples

The copy() method in Python returns a shallow copy of a list. This means it creates a new list with the same elements as the original, but the new list is a separate object in memory.

Key Points:

• Creates a new list with the same elements
• Modifications to the new list won’t affect the original
• Shallow copy means nested objects are still references to the same objects

Examples:

Example 1: Basic copy

python

original = [1, 2, 3]
copied = original.copy()

print(copied)  # Output: [1, 2, 3]
print(original is copied)  # Output: False (they are different objects)

Example 2: Modifying the copy doesn’t affect original

python

fruits = ['apple', 'banana', 'cherry']
fruit_copy = fruits.copy()

fruit_copy.append('orange')
print(fruits)      # Output: ['apple', 'banana', 'cherry']
print(fruit_copy)   # Output: ['apple', 'banana', 'cherry', 'orange']

Example 3: Shallow copy demonstration (nested lists)

python

original = [[1, 2], [3, 4]]
copied = original.copy()

copied[0][0] = 99
print(original)  # Output: [[99, 2], [3, 4]] (nested list is shared)

Example 4: Copy vs assignment

python

a = [1, 2, 3]
b = a          # assignment (same object)
c = a.copy()   # copy (new object)

a.append(4)
print(b)  # Output: [1, 2, 3, 4] (b is same as a)
print(c)  # Output: [1, 2, 3]    (c is independent)

Example 5: Copying empty list

python

empty = []
empty_copy = empty.copy()

empty_copy.append(1)
print(empty)       # Output: []
print(empty_copy)  # Output: [1]

For deep copies (where nested objects are also copied), you would use the copy.deepcopy() function from the copy module instead.